Home / 1,280.64-1,921.17-458.90

Finding the Fourth Proportional to 1,280.64, 1,921.17 and 458.90

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Solution

The fourth proportional to 1,280.64, 1,921.17 and 458.90 is: 688.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.64 : 1,921.17 = 458.90 : x
  2. Step 2: Convert to fraction form
    1,280.64/1,921.17 = 458.90/x
  3. Step 3: Cross multiply
    1,280.64x = 1,921.17 × 458.90
  4. Step 4: Simplify right side
    1,280.64x = 881,617.82
  5. Step 5: Solve for x
    x = 881,617.82/1,280.64
  6. Step 6: Final answer
    x = 688.42

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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.