Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
primary 6 | Maths
| Ratio
One Answer Below
Anyone can contribute an answer, even non-tutors.
Please help
Thank you.
At first, ratio = 3:7
Difference = 7 - 3 = 4
In 10 years, ratio = 11:19
Difference = 19 - 11 = 8
Notice that their age difference will always be the same. So, make the difference of the ratio at first the same as the one after 10 years.
3 : 7 → x2 → 6 : 14
Difference = 4 → x2 = 8
However, 11- 6 = 5
19 - 14 = 5
This is not correct as only difference between future and present is only 5 years. So, we need to multiply by 2.
Ratio at first = 6 : 14 = 12 : 28
Ratio in 10 years time = 11:19 = 22 : 38
Check:
22 - 12 = 10 (correct)
38 - 28 = 10 (correct)
See 1 Answer