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Finding the Fourth Proportional to 387.80, 531.47 and 387.16

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Solution

The fourth proportional to 387.80, 531.47 and 387.16 is: 530.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.80 : 531.47 = 387.16 : x
  2. Step 2: Convert to fraction form
    387.80/531.47 = 387.16/x
  3. Step 3: Cross multiply
    387.80x = 531.47 × 387.16
  4. Step 4: Simplify right side
    387.80x = 205,763.93
  5. Step 5: Solve for x
    x = 205,763.93/387.80
  6. Step 6: Final answer
    x = 530.59

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.