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Algebra Difficulty 1.2 Junior Find the answer Canada

Violet has one-half of the money she needs to buy her mother a necklace. After her sister gives her $30, she has three-quarters of the amount she needs. Violet’s father agrees to give her the rest. The amount that Violet’s father will give her is

Pick one

Solutions — 2

Solution 1

Violet starts with one-half of the money that she needed to buy the necklace.

After her sister gives her money, she has three-quarters of the amount that she needs.

This means that her sister gave her $\frac{3}{4}-\frac{1}{2}=\frac{1}{4}$ of the total amount that she needs.

Since she now has three-quarters of the amount that she needs, then she still needs one-quarter of the total cost.

In other words, her father will give her the same amount that her sister gave her, or $30.

Solution 2

Violet starts with one-half of the money that she needed to buy the necklace.

After her sister gives her money, she has three-quarters of the amount that she needs.

This means that her sister gave her $\frac{3}{4}-\frac{1}{2}=\frac{1}{4}$ of the total amount that she needs.

Since she now has three-quarters of the amount that she needs, then she still needs one-quarter of the total cost.

In other words, her father will give her the same amount that her sister gave her, or $30.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.