Home / 1,081.28-1,492.08-639.20

Finding the Fourth Proportional to 1,081.28, 1,492.08 and 639.20

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Solution

The fourth proportional to 1,081.28, 1,492.08 and 639.20 is: 882.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,081.28 : 1,492.08 = 639.20 : x
  2. Step 2: Convert to fraction form
    1,081.28/1,492.08 = 639.20/x
  3. Step 3: Cross multiply
    1,081.28x = 1,492.08 × 639.20
  4. Step 4: Simplify right side
    1,081.28x = 953,737.54
  5. Step 5: Solve for x
    x = 953,737.54/1,081.28
  6. Step 6: Final answer
    x = 882.04

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.