Home / 1,280.21-1,921.12-458.46

Finding the Fourth Proportional to 1,280.21, 1,921.12 and 458.46

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Solution

The fourth proportional to 1,280.21, 1,921.12 and 458.46 is: 687.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.21 : 1,921.12 = 458.46 : x
  2. Step 2: Convert to fraction form
    1,280.21/1,921.12 = 458.46/x
  3. Step 3: Cross multiply
    1,280.21x = 1,921.12 × 458.46
  4. Step 4: Simplify right side
    1,280.21x = 880,755.53
  5. Step 5: Solve for x
    x = 880,755.53/1,280.21
  6. Step 6: Final answer
    x = 687.98

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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.