# Sarin’s family attend concert at the Esplanade Part 31 (Math Question)

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The blog postings are about the Singapore Math. The readers can learn from the postings on Solving Singapore Primary School Mathematics. The blog presents the Math Concept, the Math Questions with solutions that teaches in Singapore Primary Schools. You or the kids can learn how to deal with the Math Modeling, the Math Problem Solving and the Problem Sum from Lower Primary School to Upper Primary School level. This posting is an upper primary school math question on  PercentageRatio and Problem Solving.

The story on Sarin’s family attend concert at the Esplanade you can read postings on Sarin’s family attend concert at the Esplanade in Welcome category and Sarin’s family attend concert at the Esplanade Part 2 (Math Question).

You should read also the posting on Sarin learns concept of ratio in school to understand mathematics concept of Ratio.

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

Challenge yourself with the question before look out for the given solution‼

Upper primary school mathematics question UPQ514

In the Esplanade Library, At first, the ratio of the number of adults to the number of children was 3 : 2 at first and the ratio of the number of boys to the number of girls was 1 : 3. There were 294 more adults than girls. In the afternoon, some more children visited the Esplanade Library. After that, 80 % of the people were children. How many more children visited the Esplanande Library in the afternoon?

Solution:

The ratio of visitors in the library at first,

Adults : Children = 3 : 2 = 6 : 4

Boys : Girls : Children = 1 : 3 : 4

Adults : Boys : Girls = 6 : 1 : 3

Adults more than Girls by 294 people

3 units = 294

1 unit = 98

The number of adults = 6 × 98 = 588

The number of children = 4 × 98 = 392

In the afternoon,

The percentage of adults = 100% – 80 % = 20%

20% ==> 588

80% ==> 4 × 588 = 2352

The number of children visited the library in the afternoon = 2352 – 392 = 1960

Alternative Solution(1):

Draw the model of the visitors in the Library based on the ratio given, Per the model,

3 units = 294

1 unit = 98

The number of children visited the Library in the afternoon = 20 × 98 = 1960

Alternative Solution(2):

Draw the model of the visitors in the Library based on the ratio given, From the model,

The number of adults = 2 × 294 = 588

3 units = 294

1 unit = 98

The number of children in the morning = 4 × 98 = 392

In the afternoon,

The adults became 20% and children became 80%

The model, 1 unit = 588

The number of children in the afternoon = 4 × 588 = 2352

The number of children visited the Library in the afternoon = 2352 – 392 = 1960