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Finding the Fourth Proportional to 659.78, 988.86 and 477.80

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Solution

The fourth proportional to 659.78, 988.86 and 477.80 is: 716.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.78 : 988.86 = 477.80 : x
  2. Step 2: Convert to fraction form
    659.78/988.86 = 477.80/x
  3. Step 3: Cross multiply
    659.78x = 988.86 × 477.80
  4. Step 4: Simplify right side
    659.78x = 472,477.31
  5. Step 5: Solve for x
    x = 472,477.31/659.78
  6. Step 6: Final answer
    x = 716.11

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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.