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Finding the Fourth Proportional to 520.90, 718.79 and 288.01

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Solution

The fourth proportional to 520.90, 718.79 and 288.01 is: 397.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.90 : 718.79 = 288.01 : x
  2. Step 2: Convert to fraction form
    520.90/718.79 = 288.01/x
  3. Step 3: Cross multiply
    520.90x = 718.79 × 288.01
  4. Step 4: Simplify right side
    520.90x = 207,018.71
  5. Step 5: Solve for x
    x = 207,018.71/520.90
  6. Step 6: Final answer
    x = 397.43

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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.