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Finding the Fourth Proportional to 838.50, 1,157.13 and 489.21

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Solution

The fourth proportional to 838.50, 1,157.13 and 489.21 is: 675.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.50 : 1,157.13 = 489.21 : x
  2. Step 2: Convert to fraction form
    838.50/1,157.13 = 489.21/x
  3. Step 3: Cross multiply
    838.50x = 1,157.13 × 489.21
  4. Step 4: Simplify right side
    838.50x = 566,079.57
  5. Step 5: Solve for x
    x = 566,079.57/838.50
  6. Step 6: Final answer
    x = 675.11

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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.