If Jason eats three potatoes in 20 minutes, how long, in hours, would it take for him to eat all 27 potatoes cooked by his wife? Give the rationale and then the answer.
Let's think step by step. Since 1 hour is 60 minutes, 20 minutes is 20 / 60 = 1 / 3 of an hour. Eating 3 potatoes per 20 minutes is 3 / (1 / 3) = 9 potatoes per hour. At 9 potatoes per hour, it will take Jason 27 / 9 = 3 hours to eat all of the potatoes.. The answer is: 3.

Susie babysits every day for 3 hours a day at the rate of $10 per hour. She spent 3/10 of the money she earned from last week to buy a make-up set. She then spent 2/5 of her money on her skincare products. How much is left from her earnings last week, in dollars? Give the rationale and then the answer.
Let's think step by step. Susie earned $10 x 3 = $30 per day. Last week, she earned a total of $30 x 7 = $210. She spent $210 x 3 / 10 = $63 on make - up. While she spent $210 x 2 / 5 = $84 on her skincare products. Thus, she spent a total of $63 + $84 = $147 from her earnings. Therefore, Susie is left with $210 - $147 = $63 from her earnings last week.. The answer is: 63.

Lyra bought a pair of shoes at a 20% discount. If she paid $480, how much was the original price of the pair of shoes? Give the rationale and then the answer.
Let's think step by step. Lyra only paid $480 for the pair of shoes which is only 100% - 20% = 80% of the original price. So let x be the original price. Then 0.8x = $480. Thus x = $480 / 0.8 = $600.. The answer is: 600.