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Finding the Fourth Proportional to 505.71, 696.85 and 387.69

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Solution

The fourth proportional to 505.71, 696.85 and 387.69 is: 534.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.71 : 696.85 = 387.69 : x
  2. Step 2: Convert to fraction form
    505.71/696.85 = 387.69/x
  3. Step 3: Cross multiply
    505.71x = 696.85 × 387.69
  4. Step 4: Simplify right side
    505.71x = 270,158.19
  5. Step 5: Solve for x
    x = 270,158.19/505.71
  6. Step 6: Final answer
    x = 534.22

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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.