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Finding the Fourth Proportional to 831.71, 1,247.57 and 398.57

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Solution

The fourth proportional to 831.71, 1,247.57 and 398.57 is: 597.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    831.71 : 1,247.57 = 398.57 : x
  2. Step 2: Convert to fraction form
    831.71/1,247.57 = 398.57/x
  3. Step 3: Cross multiply
    831.71x = 1,247.57 × 398.57
  4. Step 4: Simplify right side
    831.71x = 497,241.98
  5. Step 5: Solve for x
    x = 497,241.98/831.71
  6. Step 6: Final answer
    x = 597.86

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.