Home / 1,280.28-1,767.40-808.86

Finding the Fourth Proportional to 1,280.28, 1,767.40 and 808.86

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Solution

The fourth proportional to 1,280.28, 1,767.40 and 808.86 is: 1,116.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.28 : 1,767.40 = 808.86 : x
  2. Step 2: Convert to fraction form
    1,280.28/1,767.40 = 808.86/x
  3. Step 3: Cross multiply
    1,280.28x = 1,767.40 × 808.86
  4. Step 4: Simplify right side
    1,280.28x = 1,429,579.16
  5. Step 5: Solve for x
    x = 1,429,579.16/1,280.28
  6. Step 6: Final answer
    x = 1,116.61

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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.