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URL: https://nakafa.com/en/exercises/high-school/snbt/mathematical-reasoning/try-out/2026/set-1/12

Exercises: Try Out 2026 - Set 1: Real exam simulation to sharpen your skills and build confidence. - Question 12

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## Exercise 12

### Question

export const metadata = {
  title: "Question 12",
  authors: [{ name: "Nabil Akbarazzima Fatih" }],
  date: "11/23/2025",
};

A building construction project is completed in <InlineMath math="50 \text{ working days }" /> with the help of <InlineMath math="80 \text{ workers }" />. Kardi, as one of the workers, makes a plaster mixture of cement and sand every day with a ratio of <InlineMath math="1:5" />.

To make the plaster material, the amount of cement required by Kardi to be mixed with <InlineMath math="0.24 \text{ cubic meters}" /> of sand is ... kg. (Use sand density <InlineMath math="1{,}400 \text{ kg/m}^3" />).



### Choices

- [ ] $$44.2$$
- [ ] $$51.8$$
- [ ] $$56.4$$
- [ ] $$63.5$$
- [x] $$67.2$$

### Answer & Explanation

export const metadata = {
  title: "Solution for Question 12",
  authors: [{ name: "Nabil Akbarazzima Fatih" }],
  date: "11/23/2025",
};

We will calculate the weight of the sand first, then use the mixture ratio to determine the required weight of cement.

#### Calculating Sand Weight

Given the volume of sand is <InlineMath math="0.24 \text{ m}^3" /> and the density of sand is <InlineMath math="1{,}400 \text{ kg/m}^3" />.

<BlockMath math="\text{Sand Weight} = \text{Volume} \times \text{Density}" />

We substitute the values:

<MathContainer>
  <BlockMath math="\text{Sand Weight} = 0.24 \times 1{,}400" />
  <BlockMath math="\text{Sand Weight} = 336 \text{ kg}" />
</MathContainer>

#### Calculating Cement Weight

Given the mixture ratio of Cement : Sand is <InlineMath math="1 : 5" />. This means for every <InlineMath math="5" /> parts of sand weight, <InlineMath math="1" /> part of cement weight is needed.

<BlockMath math="\text{Cement Weight} = \frac{1}{5} \times \text{Sand Weight}" />

We calculate the cement weight:

<MathContainer>
  <BlockMath math="\text{Cement Weight} = \frac{1}{5} \times 336" />
  <BlockMath math="\text{Cement Weight} = 67.2 \text{ kg}" />
</MathContainer>

So, the amount of cement required is <InlineMath math="67.2 \text{ kg}" />.



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