1 · MATH-5B-C15-REVIEW-Q01
In a 100-square grid, 20 cells are shaded. Give percent and simplest fraction.
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Answer: 20% and 1/5
20/100=1/5.
Singapore Math 5B · Original independent course
Chapter 15 Review
Formative chapter review. Work independently, then reveal the feedback.
Original assessment
2 · MATH-5B-C15-REVIEW-Q02
Explain why a 100-square model shading 20 squares represents 20% rather than 20/10 of the whole.
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Answer: 20%
Percent counts out of exactly 100 equal cells.
3 · MATH-5B-C15-REVIEW-Q03
Reduce the fraction represented by 30 percent to lowest terms.
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Answer: 3/10
30/100 simplifies to 3/10.
4 · MATH-5B-C15-REVIEW-Q04
A fraction is 3/10. Write its equivalent percent and explain the base.
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Answer: 30%
One whole is 100 percent; scale numerator and denominator accordingly.
5 · MATH-5B-C15-REVIEW-Q05
Convert decimal 0.4 to percent; explain multiplication by 100.
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Answer: 40%
0.4×100%=40%.
6 · MATH-5B-C15-REVIEW-Q06
A display says 40% full. What decimal part of its capacity is used?
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Answer: 0.4
40/100=0.4.
7 · MATH-5B-C15-REVIEW-Q07
Turn fraction 1/2 into a percent using a denominator of 100.
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Answer: 50%
1/2×100=50%.
8 · MATH-5B-C15-REVIEW-Q08
In a grid of 8 equal cells, 4 are shaded. What percentage is shaded?
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Answer: 50%
4/8=1/2=50%.
9 · MATH-5B-C15-REVIEW-Q09
An event has 500 attendees; 60% choose lunch. Find the count.
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Answer: 300
500×60/100=300.
10 · MATH-5B-C15-REVIEW-Q10
300 attendees represent 60% of a club. How many attend in all?
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Answer: 500
300 ÷ (60/100)=500.
11 · MATH-5B-C15-REVIEW-Q11
A budget of $520 rises by 70%. Calculate both the increase and revised total.
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Answer: $364 increase; $884 total
70% of 520 is 364; add to original $520.
12 · MATH-5B-C15-REVIEW-Q12
An event fee of $520 is reduced by 70%. What fee remains?
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Answer: $156
Find 70% of the original price, then subtract.