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Finding the Fourth Proportional to 663.50, 915.63 and 387.50

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Solution

The fourth proportional to 663.50, 915.63 and 387.50 is: 534.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.50 : 915.63 = 387.50 : x
  2. Step 2: Convert to fraction form
    663.50/915.63 = 387.50/x
  3. Step 3: Cross multiply
    663.50x = 915.63 × 387.50
  4. Step 4: Simplify right side
    663.50x = 354,806.63
  5. Step 5: Solve for x
    x = 354,806.63/663.50
  6. Step 6: Final answer
    x = 534.75

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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.