Finding the Fourth Proportional to 671.72, 1,007.74 and 287
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Solution
The fourth proportional to 671.72, 1,007.74 and 287 is: 430.57
Step by Step Solution
- Step 1: Write the proportion equation
671.72 : 1,007.74 = 287 : x - Step 2: Convert to fraction form
671.72/1,007.74 = 287/x - Step 3: Cross multiply
671.72x = 1,007.74 × 287 - Step 4: Simplify right side
671.72x = 289,221.38 - Step 5: Solve for x
x = 289,221.38/671.72 - Step 6: Final answer
x = 430.57
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.