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Finding the Fourth Proportional to 615.04, 921.12 and 520

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Solution

The fourth proportional to 615.04, 921.12 and 520 is: 778.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.04 : 921.12 = 520 : x
  2. Step 2: Convert to fraction form
    615.04/921.12 = 520/x
  3. Step 3: Cross multiply
    615.04x = 921.12 × 520
  4. Step 4: Simplify right side
    615.04x = 478,982.40
  5. Step 5: Solve for x
    x = 478,982.40/615.04
  6. Step 6: Final answer
    x = 778.78

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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.