Question

The ratio of the number of biscuits that Andy and Betty had was 2: 5. After

Andy bought 24 more biscuits, the ratio became 16:10. If there were 6 biscuits
in a pack, how many packs of biscuits would Betty have to buy so that they
would have the same number of biscuits in the end?
(Answer step-by-step)

Answer 1

equation 1 > a:b=2:5 > a=2b/5

equation 2 > a+24 : b = 16 : 10 > substitute a from eq1

(2b/5 + 24)/b = 16/10 > if we cross multiply this

4b + 240 = 16b

240 = 12b

b = 20

from eq1 a=2b/5

a=(2×20)/5

a=8

if Andy bought 24 biscuits it means he has 32 biscuits

since Betty has 20 she needs 12 more biscuits, which means 2 packs.

hence answer is 2 packs of biscuits