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Finding the Fourth Proportional to 838.31, 1,157.07 and 489.20

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Solution

The fourth proportional to 838.31, 1,157.07 and 489.20 is: 675.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.31 : 1,157.07 = 489.20 : x
  2. Step 2: Convert to fraction form
    838.31/1,157.07 = 489.20/x
  3. Step 3: Cross multiply
    838.31x = 1,157.07 × 489.20
  4. Step 4: Simplify right side
    838.31x = 566,038.64
  5. Step 5: Solve for x
    x = 566,038.64/838.31
  6. Step 6: Final answer
    x = 675.21

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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.