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Finding the Fourth Proportional to 520.80, 777.24 and 478.80

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Solution

The fourth proportional to 520.80, 777.24 and 478.80 is: 714.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 777.24 = 478.80 : x
  2. Step 2: Convert to fraction form
    520.80/777.24 = 478.80/x
  3. Step 3: Cross multiply
    520.80x = 777.24 × 478.80
  4. Step 4: Simplify right side
    520.80x = 372,142.51
  5. Step 5: Solve for x
    x = 372,142.51/520.80
  6. Step 6: Final answer
    x = 714.56

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.