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Finding the Fourth Proportional to 891.70, 1,337.55 and 405.70

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Solution

The fourth proportional to 891.70, 1,337.55 and 405.70 is: 608.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.70 : 1,337.55 = 405.70 : x
  2. Step 2: Convert to fraction form
    891.70/1,337.55 = 405.70/x
  3. Step 3: Cross multiply
    891.70x = 1,337.55 × 405.70
  4. Step 4: Simplify right side
    891.70x = 542,644.04
  5. Step 5: Solve for x
    x = 542,644.04/891.70
  6. Step 6: Final answer
    x = 608.55

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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.