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Finding the Fourth Proportional to 520.86, 718.75 and 287.99

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Solution

The fourth proportional to 520.86, 718.75 and 287.99 is: 397.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.86 : 718.75 = 287.99 : x
  2. Step 2: Convert to fraction form
    520.86/718.75 = 287.99/x
  3. Step 3: Cross multiply
    520.86x = 718.75 × 287.99
  4. Step 4: Simplify right side
    520.86x = 206,988.50
  5. Step 5: Solve for x
    x = 206,988.50/520.86
  6. Step 6: Final answer
    x = 397.40

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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.