The blog postings are about the Singapore Math. The readers can learn from the postings about Solving Singapore Primary School Mathematics. The blog presenting the Math Concept, Math Questions with solutions that teaches in Singapore Primary Schools. You or the kids can learn the skills of dealing with Math Modeling, Problem Sum from Lower Primary School to Upper Primary School level after reading the postings. This posting is an upper primary school math question on Percentage, Fraction , Ratio and Problem Solving.

You can read posting **Sarin and his coin bank** on the story of coin bank.

Read the posting on **Sarin learns Average Number, Percentage and and Charting in school (Math Concept)** to understand the concept of Percentage**.**

Read also the postings on **Sarin learns concept of ratio in school** and **Sarin learns the concept of Fraction (mathematics concept)** to understand Ratio and Fraction.

*Challenge yourself with the Question before look out for the given solution‼!*

**Upper primary school mathematics question UPQ316**

Sarin and his sister Fatimah have some money in their coin bank. 30% of Fatimah’s sum of money is 50% of Sarin’s sum of money. If Sarin has $72, how much money has Fatimah?

Solution:

Sarin has $72

50% of Sarin’s sum of money = $72 × 50/100 = $36

30% of Fatimah’s sum of money = $36

Fatimah’s sum of money = $36 × 100/30 = $120

Alternative Solution(1):

Visual using Math Model

30% of Fatimah’s sum of money is 3/10 fraction of Fatimah’s sum of money

50% of Sarin’s sum of money is ½ fraction of Sarin’s sum of money

Per the model

6 units = 72

1 unit = 12

The sum of money Fatimah has = 10 × 12 = $120

Alternative Solution(2):

The fraction of 30% of Fatimah’s sum of money = 30/100 = 3/10

The fraction of 50% of Sarin’s sum of money = 50/100 = ½ = 3/6

The ratio of Fatimah’s sum of money to Sarin’s sum of money = 10 : 6

Sarin’s sum of money = $72

6 units = 72

1 unit = 12

The sum of money that Fatimah has = 10 × 12 = $120