Grade 7 Math- Midterm Review Answer Key

Transcription

1 Chapter -Operations on Decimal Numbers Grade 7 Math- Midterm Review nswer Key ) Place the decimal point in each answer without calculating. a =4.73 b. $9.4+$6.99+$.49=$6.6 c. $33.6-$4=$9.6 d =46. ) Calculate a b c. $3.99+$.8+$3 d $3.99 $.8 $3 $6.79 3) steel bar is cut into 3 pieces with lengths 36.4 cm, 4.6 cm and 3. cm. How long was the bar? The bar was 9.3cm long. 4) Without calculating the answer, place the decimal point in the correct position. a = 8.96 b = ) Calculate a b. 4 / c

2 6) German Shepherd has a mass of 4 kg. Great Dane has a mass.8 times that amount. What is the mass of the Great Dane? 4kg kg 7) Without calculating the answer, place the decimal point in the correct position. a =.4 b = 8. 8) Calculate a.. 6 b c ) If juice boxes cost $.7, how much does one juice box cost? $.34 $.7 One juice costs $.34 ) What is the value of each expression? a

3 b. 8 (.3+ 7.) ( ) ) Rewrite the statement using brackets to make a true statement. 8 $. + 3 $8. + $6. = $ + 3 $8. + $6. = $ + $47. + $3. = $47. + $3. = $6 is collected ( ) 9.= 46. ) Clover ar drama group is putting on a production of Legally londe. Ticket prices are: dults: $. Seniors: $8. Students: $6. If 8 adults, 3 seniors and students attend the first performance, how much admission is collected? 8 $. + 3 $8. + $6. = $ + 3 $8. + $6. = $ + $47. + $3. = $47. + $3. = $6 is collected

4 Chapter 4-Fractions, Decimals, and Percents ) What is % of each quantity? a. 34 marbles b. $74.8 % of 34 (use benchmarks) %=34 % of $74.8 (use benchmarks) %=$74.8 %=67 %=$37.4 ) What is % of each quantity? a. 68 flowers b. 4 min % of 68 % of 4 %=68 %=34 %=4 %= %=7 %=. 3) What is % of each quantity? a. 34 cm b. $89. % of 34 Divide by ten therefore move % of $89. $89. decimal point one place to $8.9 the left ) Find each amount mentally? a. 7% of 44 b. 3% of 4 % = 44 %= %= %+%=7% +=33 % = 4 %= %=6 %=4 %+%=3% 6+4=84 ) Change each percent to a decimal number. a. 38% b. 67% 38% Divide by therefore move decimal point places to the left 38%=.38 67%=.67

5 6) Write the following numbers in descending order..,.4,.4.4,.,.4,4%,.4.4,,4% 7) ccording to an article in the newspaper, 3% of Sherwood Park residents like winter. If the population of Sherwood Park is 8, how many people like winter? 3% of ) Use a calculator to change each 8 fraction people to a decimal like winter number. Round to the place value indicated a. ( tenths ) b. ( thousandths ) 89 3 numerator denominator 3 = =.68668=.68 9) Write each repeating decimal number using bar notation. a.. =. b.. =. ) Change each fraction to a repeating decimal. Then use bar notation to show the repeating part. a. =.83 b. 4 = ) Estimate each of the following as a percent. a. 36 out of 7 b. out of 3 % = 7 %=3 Estimate is about % % = 3 %= %=7 %=3 %= %= = %+%+%+%=4% ) Change each decimal number to a fraction in lowest terms. a..9 b..8.9 Read the decimal. It says 8 hundredths It says 9 hundredths 8 = 9 9 =

6 3) There are 8 girls and 9 boys in Sherwood Park Day Care. Estimate the percent of the children in the day care that are girls. 8 out of 4 are girls % = 4 %=7 %=3 %=4 %=7 %=.4 7+4=84 %+=6% pproximately 8% of the children in the day care are girls. 4) Naomi is the manager of a restaurant in Yellowknife. Her annual salary is $4 9.. fter a performance review her boss awards her a pay raise of 8.% a. What is the amount of her salary increase? 8.% of $ $4 69 $ $ is the amount of her salary increase. b. What is her new annual salary? $4 69+$348.74=$ Her new anual salary is $ Chapter 6/7-Fraction Operations ) Use divisibility rules to list the factors of the following numbers: a. 36 b. 8,,3,4,6,9,,8,36,,4,7,4,8 ) What are the common factors for each pair of numbers? a. 4 and b. 4 and 4-,,4 4-,,3,4,6,8,,4 -,,3,4,6, -,3,, The common factors of 4 and The common factors of 4 and are and 3 are,, & 4 3) Write each fraction in lowest terms. a = = b = 3 4) Determine the sum of each fraction statement. Write each answer in lowest terms. a. 3 + = b = c

7 ) Determine the difference. Write your answer in lowest terms. 4 3 = c a. b ) Determine a common denominator for each set of fractions. Then use the common denominator to write equivalent fractions. a. and 6 4 Common denominator is b., and 7 3 Common denominator is = ) Determine the sum. Write your answers in lowest terms. a. + 3 b. + c Common denominator is 8 Common denominator is Common denominator is = = = 8) Determine the difference. Write your answers in lowest terms. a. 3 b. c Common denominator is 8 Common denominator is 6 Common denominator is = - = - = ) Determine the sum. Write your answers in lowest terms. a = ) Jenny studied in total? + b. 4 + c hours for her math test and = 7 = 7 h for her science test. How long did she study

8 = ) Determine the difference. Write you answers in lowest terms. a. - - b =4 3 c ) pie recipe calls for 3 packages of Saskatoon berries. Julia has 3 packages. How much more does she need? Julia needs more packages. 6 Chapter -Probability ) What is the definition of probability? Probability is the likelihood or chance of an event occurring. ) What is an outcome? n outcome is one possible result of a probability experiment. 3) What is a sample space? sample space is all possible outcomes of an experiment. 4) spinner with three equal sections is spun once. E P L

9 a. How many outcomes are possible? 3 b. What is the probability of spinning a vowel? Express your answer as a fraction, a ratio and a percent.,:3,33.3% 3 ) Jeremy chooses a tile and spins the spinner. hungry sleepy bear monkey playful angry tiger a. Organize the outcomes of these two events in a table. SPIN Tiger ear Monkey Tile Choice Hungry Hungry, tiger Hungry, bear Hungry, monkey Playful Playful, tiger Playful, bear Playful, monkey ngry ngry, tiger ngry, bear ngry, monkey b. What is the sample space for this experiment? Each square contains ordered pairs, e.g., (hungry, tiger), (hungry, bear). ll of the ordered pairs in the table together represent the sample space. 6) lan flips a coin and chooses one of three marbles: black (), yellow (Y) and red (R) a. Draw a tree diagram to organize the outcomes of these two events. (Head, ) Head Y (Head, Y) R (Head, R) (Tail, ) Tail (Tail, Y) Y (Tail, R) COIN MRLE COLOR OUTCOMES b. What is the sample space for this experiment? R

10 The sample space is contained in the outcome column, e.g., (Head, ), (Head, Y). 7) Joey randomly picks a marble from a bag containing one red, one green, one yellow, one purple, and one black marble and spins a spinner with five equal sections labeled,, 3, 4, and. a. Create a table to organize the outcomes for these two events. SPINNER 3 4 Purple Purple, Purple, Purple,3 Purple,4 Purple,3 lack lack, lack, lack,3 lack,4 lack, Marble Yellow Yellow, Yellow, Yellow,3 Yellow,4 Yellow, Green Green, Green, Green,3 Green,4 Green, Red Red, Red, Red,3 Red,4 Red, b. What is P(green,) 4% c. What is P(yellow, or 3) 8% d. What is the probability of selecting a green marble and spinning a number that is less than 3? P(green, a number less than 3) 8% 8) Margot spins the spinner and rolls the cube labeled,, C, D, E, F. D E C a. Create a tree diagram to organize the sample space. C D Outcome (,) (,)

11 SPINNER C E F C D E F C D E F CUE (,C) (,D) (,E) (,F) (,) (,) (,C) (,D) (,E) (,F) (C,) (C,) (C,C) (C,D) (C,E) (C,F) b. What is the probability of spinning an and rolling an? P(, ) = or.6% 8 c. What is the probability of spinning and rolling the same letter? There are three favorable outcomes: (,), (,), (C,C) 3 P(spinning and rolling the same letter) = or 6.7% 8 9) What is the difference between theoretical and experimental probability? Theoretical probability is the expected probability of an event occurring and experimental probability is the probability of an event occurring based on experimental results. ) spinner with 4 equal regions labeled,, C, and D is spun times. The following tally chart shows the experimental outcomes. Write any probabilities in fraction form. llll llll l C llll ll D lll a. From the tally chart, what is the experimental probability of spinning C? P(C)= 7 b. What is the theoretical probability of spinning C? P(C)= 4 c. Explain why the answers for a) and b) are not the same. The probability in a) is based on the results of an experiment.

12 Chapter 9-dd & Subtract Integers ) What is a zero pair? zero pair is a pair of integer chips, with one chip representing + and one chip representing The pair represents because + = ) What is an opposite integer? Opposite integers are two integers with the same numeral, but different signs. Eg. +, - 3) What integer statement does each diagram represent? a = 3 b. _ = 4 4) Find the sum. a. 4+ b. 3 + = 8 c. 3+ = What do I have more of? Positives How many more? - 4+ = d. + 3= e = f = ) What integer is 8 more than its opposite? 4 because 4 4= 8 6) What is the 3- word rule we use for subtraction of integers? dd the opposite 7) What subtraction statement does the diagram represent? _ = _

13 8) Determine each difference. a. 6 4 b = dd the opposite c = 4+ 8= 4 dd the opposite dd the opposite 9) The lowest temperature recorded in Canada was 63 C at Snag, Yukon Territory. The highest temperature recorded in Canada was 4 C at Midale, Saskatchewan. What is the difference between these temperatures? C The difference in temperature was 8 C. ) Mauna Kea is a mountain in Hawaii. The base of the mountain is 633m below the surface of the ocean. The mountain peak is 47m above the surface of the ocean. Calculate the height of the mountain. 47m 633 = 47m+ 633 = 3m The height of Mauna Kea is 3m.