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Finding the Fourth Proportional to 624.64, 861.88 and 388.65

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Solution

The fourth proportional to 624.64, 861.88 and 388.65 is: 536.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    624.64 : 861.88 = 388.65 : x
  2. Step 2: Convert to fraction form
    624.64/861.88 = 388.65/x
  3. Step 3: Cross multiply
    624.64x = 861.88 × 388.65
  4. Step 4: Simplify right side
    624.64x = 334,969.66
  5. Step 5: Solve for x
    x = 334,969.66/624.64
  6. Step 6: Final answer
    x = 536.26

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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.