To solve the problem, we start by analyzing the ratio of Olivia's and Sylvia's allowances, which is 2:3. This means for every 2 parts Olivia receives, Sylvia receives 3 parts.
Given that Sylvia receives $21, we need to figure out how much each "part" of the allowance is worth first.
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Set up the parts based on the ratio:
- Let Olivia's parts = 2
- Let Sylvia's parts = 3
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Find the value of one part: Since Sylvia's allowance represents 3 parts and she gets $21, we can calculate the value of one part by dividing her amount by 3: \[ \text{Value of one part} = \frac{21}{3} = 7 \]
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Now, calculate Olivia's allowance: Olivia receives 2 parts. Therefore: \[ \text{Olivia's allowance} = 2 \times 7 = 14 \]
So, Olivia received $14.
Tape Diagram Representation
To visualize this with a tape diagram:
Olivia: |---|---| (2 parts)
Sylvia: |---|---|---|---|---| (3 parts)
Each segment = $7
Olivia: | $7 | $7 | (Total = $14)
Sylvia: | $7 | $7 | $7 | (Total = $21)
In summary, Olivia received $14, and this is consistent with the initial ratio of their allowances.