Home / 1,331.60-1,999.80-1,288.40

Finding the Fourth Proportional to 1,331.60, 1,999.80 and 1,288.40

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Solution

The fourth proportional to 1,331.60, 1,999.80 and 1,288.40 is: 1,934.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,331.60 : 1,999.80 = 1,288.40 : x
  2. Step 2: Convert to fraction form
    1,331.60/1,999.80 = 1,288.40/x
  3. Step 3: Cross multiply
    1,331.60x = 1,999.80 × 1,288.40
  4. Step 4: Simplify right side
    1,331.60x = 2,576,542.32
  5. Step 5: Solve for x
    x = 2,576,542.32/1,331.60
  6. Step 6: Final answer
    x = 1,934.92

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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.