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A Drink of Water
Age
14 to 16
Short
Challenge Level
Secondary curriculum
Problem
Solutions
Answer
: Ross drinks 300 ml and Rachel drinks 450 ml
Using ratio
If Rachel drinks 50% more than Ross, the amount they drink is in the ratio 3 : 2
750 $\div$ 5 = 150
Rachel: 150 ml $\times$ 3 = 450 ml
Ross: 150 ml $\times$ 2 = 300 ml
Using percentage
Ross 100%
Rachel 150%
Total 250% = 750 ml
25% = 75 ml
100% = 300 ml Ross
150% = 450 ml Rachel
This problem is taken from the
UKMT Mathematical Challenges
.
You can find more short problems, arranged by curriculum topic, in our
short problems collection
.