Walt: Find fractions, decimals, and percentages of amounts expressed as whole numbers, simple fractions, and decimals.
Answer and explanation:
The first sweatshirt is cheaper than the second one because 30% of 60 is 42 and 40% off 72 dollars is 43.20. The first sweatshirt is 1.20 cheaper than the second one.
The second jacket is cheaper because 20% off 96 is 76.80 and 30% of 120 is 84. The second jacket is cheaper by 7.20.
The first jeans is cheaper because 30% of 48 is 33.60 and 45% off 68 is 37.40. The first jeans are cheaper by 3.80.
The second tracksuit is cheaper because 25% off 64 is 48 and 30% of 86 is 60.2. The second tracksuit is cheaper by 22.20.
The least you could spent if you brought one of each clothing item would be 200.40 and the most would be 224.80. You would save 24.40.
I figured it out by figuring out what the percent is as a fractions, timing it by the cost and dividing by the fractions denominator. Then misusing the total from the cost.
The thing I found most challenging was using multiplication and division strategies to estimate and solve problems with fractions, because it was hard to found a strategy that worked.
Here were the strategies we did:
- Use multiplication and division strategies to estimate and solve problems with fractions, eg. 11 ÷ 3 = 1 1/3
- Find a fraction of another fraction by multiplying. eg. 3/4 x 5/2 = 15/8, 15/8 = 1 7/8
- Describe and show renaming tenths, hundredths, thousandths as decimal fractions and relate them to place value order, like 2/100 = 0.02
- Work out and explain percentages of simple amounts