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Finding the Fourth Proportional to 723.88, 1,000.38 and 642.88

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Solution

The fourth proportional to 723.88, 1,000.38 and 642.88 is: 888.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    723.88 : 1,000.38 = 642.88 : x
  2. Step 2: Convert to fraction form
    723.88/1,000.38 = 642.88/x
  3. Step 3: Cross multiply
    723.88x = 1,000.38 × 642.88
  4. Step 4: Simplify right side
    723.88x = 643,124.29
  5. Step 5: Solve for x
    x = 643,124.29/723.88
  6. Step 6: Final answer
    x = 888.44

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Double scale
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1.5x scale

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.