Home / 1,311.28-1,966.92-478.40

Finding the Fourth Proportional to 1,311.28, 1,966.92 and 478.40

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Solution

The fourth proportional to 1,311.28, 1,966.92 and 478.40 is: 717.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,311.28 : 1,966.92 = 478.40 : x
  2. Step 2: Convert to fraction form
    1,311.28/1,966.92 = 478.40/x
  3. Step 3: Cross multiply
    1,311.28x = 1,966.92 × 478.40
  4. Step 4: Simplify right side
    1,311.28x = 940,973.96
  5. Step 5: Solve for x
    x = 940,973.96/1,311.28
  6. Step 6: Final answer
    x = 717.60

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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.