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Finding the Fourth Proportional to 611.71, 917.13 and 286.90

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Solution

The fourth proportional to 611.71, 917.13 and 286.90 is: 430.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.71 : 917.13 = 286.90 : x
  2. Step 2: Convert to fraction form
    611.71/917.13 = 286.90/x
  3. Step 3: Cross multiply
    611.71x = 917.13 × 286.90
  4. Step 4: Simplify right side
    611.71x = 263,123.16
  5. Step 5: Solve for x
    x = 263,123.16/611.71
  6. Step 6: Final answer
    x = 430.14

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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.