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Finding the Fourth Proportional to 898.80, 1,240.43 and 505.90

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Solution

The fourth proportional to 898.80, 1,240.43 and 505.90 is: 698.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    898.80 : 1,240.43 = 505.90 : x
  2. Step 2: Convert to fraction form
    898.80/1,240.43 = 505.90/x
  3. Step 3: Cross multiply
    898.80x = 1,240.43 × 505.90
  4. Step 4: Simplify right side
    898.80x = 627,538.89
  5. Step 5: Solve for x
    x = 627,538.89/898.80
  6. Step 6: Final answer
    x = 698.19

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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.