At a school fair, Priya bought cans of soda and bottles of juice. She bought 35 as many bottles of juice as cans of soda. Each bottle of juice cost 23 as much as each can of soda. Each can of soda cost $3.60. She spent $216 more on the cans of soda than on the bottles of juice.
- How much did each bottle of juice cost?
- How many bottles of juice did she buy?
Need a hint?
For (b), write the number of cans and bottles as units of a ratio, then find how much one unit of each costs.
Worked answer
- (a) Each bottle costs 23 of $3.60.
- (a) $3.60 ÷ 3 = $1.20.
- (a) $1.20 × 2 = $2.40, so each bottle costs $2.40.
- (b) Let cans be 5 units and bottles be 3 units.
- (b) Cans cost 5 × $3.60 = $18.00 per unit; bottles cost 3 × $2.40 = $7.20 per unit.
- (b) Difference per unit = $18.00 − $7.20 = $10.80.
- (b) Number of units = $216 ÷ $10.80 = 20.
- (b) Bottles = 3 × 20 = 60.
The mistake this question tests
Stopped at one part in ratio
Many pupils take 35 of the cost of the cans instead of 35 of the number of cans, or forget that the bottles are the cheaper item when finding the difference.
How to fix it at home →More PSLE fractions questions
A zoo had 90 more visitors on Sunday than on Saturday
See the answer →Short answer · 2mA community centre kept exercise books in Box R and Box S
See the answer →Structured · 3mAt a night market, Stall X sold 2/3 of its keychains, Stall Y sold 1/4 of its keychains and Stall Z sold 1/2…
See the answer →Structured · 4mAt a science centre on a Saturday, the number of men is 1/3 of the number of women
See the answer →Structured · 5mNurul bought some ferns and cacti for the school garden
See the answer →Structured · 4mClass 6B had 24 more pupils than Class 6A on a school camp
See the answer →Practise PSLE fractions until the mistakes stop.
Three PSLE questions, free, no sign-up. You’ll see exactly where the marks went. Then 7 days of everything for S$4.99.