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Finding the Fourth Proportional to 520.71, 718.58 and 287.84

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Solution

The fourth proportional to 520.71, 718.58 and 287.84 is: 397.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.71 : 718.58 = 287.84 : x
  2. Step 2: Convert to fraction form
    520.71/718.58 = 287.84/x
  3. Step 3: Cross multiply
    520.71x = 718.58 × 287.84
  4. Step 4: Simplify right side
    520.71x = 206,833.19
  5. Step 5: Solve for x
    x = 206,833.19/520.71
  6. Step 6: Final answer
    x = 397.21

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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.