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Finding the Fourth Proportional to 898.75, 1,240.35 and 505.78

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Solution

The fourth proportional to 898.75, 1,240.35 and 505.78 is: 698.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    898.75 : 1,240.35 = 505.78 : x
  2. Step 2: Convert to fraction form
    898.75/1,240.35 = 505.78/x
  3. Step 3: Cross multiply
    898.75x = 1,240.35 × 505.78
  4. Step 4: Simplify right side
    898.75x = 627,344.22
  5. Step 5: Solve for x
    x = 627,344.22/898.75
  6. Step 6: Final answer
    x = 698.02

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Double scale
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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.