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Finding the Fourth Proportional to 640.80, 882.24 and 542.40

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Solution

The fourth proportional to 640.80, 882.24 and 542.40 is: 746.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.80 : 882.24 = 542.40 : x
  2. Step 2: Convert to fraction form
    640.80/882.24 = 542.40/x
  3. Step 3: Cross multiply
    640.80x = 882.24 × 542.40
  4. Step 4: Simplify right side
    640.80x = 478,526.98
  5. Step 5: Solve for x
    x = 478,526.98/640.80
  6. Step 6: Final answer
    x = 746.76

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1.5x scale

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.