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Finding the Fourth Proportional to 520.64, 718.42 and 287.80

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Solution

The fourth proportional to 520.64, 718.42 and 287.80 is: 397.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.64 : 718.42 = 287.80 : x
  2. Step 2: Convert to fraction form
    520.64/718.42 = 287.80/x
  3. Step 3: Cross multiply
    520.64x = 718.42 × 287.80
  4. Step 4: Simplify right side
    520.64x = 206,761.28
  5. Step 5: Solve for x
    x = 206,761.28/520.64
  6. Step 6: Final answer
    x = 397.13

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.