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Finding the Fourth Proportional to 728.98, 1,088.81 and 631.78

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Solution

The fourth proportional to 728.98, 1,088.81 and 631.78 is: 943.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.98 : 1,088.81 = 631.78 : x
  2. Step 2: Convert to fraction form
    728.98/1,088.81 = 631.78/x
  3. Step 3: Cross multiply
    728.98x = 1,088.81 × 631.78
  4. Step 4: Simplify right side
    728.98x = 687,888.38
  5. Step 5: Solve for x
    x = 687,888.38/728.98
  6. Step 6: Final answer
    x = 943.63

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.