Finding the Fourth Proportional to 639.72, 958.86 and 297
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Solution
The fourth proportional to 639.72, 958.86 and 297 is: 445.17
Step by Step Solution
- Step 1: Write the proportion equation
639.72 : 958.86 = 297 : x - Step 2: Convert to fraction form
639.72/958.86 = 297/x - Step 3: Cross multiply
639.72x = 958.86 × 297 - Step 4: Simplify right side
639.72x = 284,781.42 - Step 5: Solve for x
x = 284,781.42/639.72 - Step 6: Final answer
x = 445.17
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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.