Home / 1,280.38-1,921.08-458.74

Finding the Fourth Proportional to 1,280.38, 1,921.08 and 458.74

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Solution

The fourth proportional to 1,280.38, 1,921.08 and 458.74 is: 688.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.38 : 1,921.08 = 458.74 : x
  2. Step 2: Convert to fraction form
    1,280.38/1,921.08 = 458.74/x
  3. Step 3: Cross multiply
    1,280.38x = 1,921.08 × 458.74
  4. Step 4: Simplify right side
    1,280.38x = 881,276.24
  5. Step 5: Solve for x
    x = 881,276.24/1,280.38
  6. Step 6: Final answer
    x = 688.29

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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.