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Finding the Fourth Proportional to 688.38, 951.76 and 657.78

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Solution

The fourth proportional to 688.38, 951.76 and 657.78 is: 909.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.38 : 951.76 = 657.78 : x
  2. Step 2: Convert to fraction form
    688.38/951.76 = 657.78/x
  3. Step 3: Cross multiply
    688.38x = 951.76 × 657.78
  4. Step 4: Simplify right side
    688.38x = 626,048.69
  5. Step 5: Solve for x
    x = 626,048.69/688.38
  6. Step 6: Final answer
    x = 909.45

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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.