Home / 2,139.32-2,951.68-1,288.80

Finding the Fourth Proportional to 2,139.32, 2,951.68 and 1,288.80

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Solution

The fourth proportional to 2,139.32, 2,951.68 and 1,288.80 is: 1,778.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,139.32 : 2,951.68 = 1,288.80 : x
  2. Step 2: Convert to fraction form
    2,139.32/2,951.68 = 1,288.80/x
  3. Step 3: Cross multiply
    2,139.32x = 2,951.68 × 1,288.80
  4. Step 4: Simplify right side
    2,139.32x = 3,804,125.18
  5. Step 5: Solve for x
    x = 3,804,125.18/2,139.32
  6. Step 6: Final answer
    x = 1,778.19

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1.5x scale

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.