Home / 1,280.45-1,920.40-458.77

Finding the Fourth Proportional to 1,280.45, 1,920.40 and 458.77

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Solution

The fourth proportional to 1,280.45, 1,920.40 and 458.77 is: 688.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.45 : 1,920.40 = 458.77 : x
  2. Step 2: Convert to fraction form
    1,280.45/1,920.40 = 458.77/x
  3. Step 3: Cross multiply
    1,280.45x = 1,920.40 × 458.77
  4. Step 4: Simplify right side
    1,280.45x = 881,021.91
  5. Step 5: Solve for x
    x = 881,021.91/1,280.45
  6. Step 6: Final answer
    x = 688.06

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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.