Home / 800.23-1,200.28-280.17

Finding the Fourth Proportional to 800.23, 1,200.28 and 280.17

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Solution

The fourth proportional to 800.23, 1,200.28 and 280.17 is: 420.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.23 : 1,200.28 = 280.17 : x
  2. Step 2: Convert to fraction form
    800.23/1,200.28 = 280.17/x
  3. Step 3: Cross multiply
    800.23x = 1,200.28 × 280.17
  4. Step 4: Simplify right side
    800.23x = 336,284.86
  5. Step 5: Solve for x
    x = 336,284.86/800.23
  6. Step 6: Final answer
    x = 420.24

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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.