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Finding the Fourth Proportional to 628.80, 868.17 and 471.78

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Solution

The fourth proportional to 628.80, 868.17 and 471.78 is: 651.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 868.17 = 471.78 : x
  2. Step 2: Convert to fraction form
    628.80/868.17 = 471.78/x
  3. Step 3: Cross multiply
    628.80x = 868.17 × 471.78
  4. Step 4: Simplify right side
    628.80x = 409,585.24
  5. Step 5: Solve for x
    x = 409,585.24/628.80
  6. Step 6: Final answer
    x = 651.38

Related Problems

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Half scale
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Double scale
Find fourth proportional to 629.80, 869.55 and 472.78
Similar ratio
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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.