Home / 1,931.80-2,909.04-1,387.78

Finding the Fourth Proportional to 1,931.80, 2,909.04 and 1,387.78

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Solution

The fourth proportional to 1,931.80, 2,909.04 and 1,387.78 is: 2,089.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,931.80 : 2,909.04 = 1,387.78 : x
  2. Step 2: Convert to fraction form
    1,931.80/2,909.04 = 1,387.78/x
  3. Step 3: Cross multiply
    1,931.80x = 2,909.04 × 1,387.78
  4. Step 4: Simplify right side
    1,931.80x = 4,037,115.32
  5. Step 5: Solve for x
    x = 4,037,115.32/1,931.80
  6. Step 6: Final answer
    x = 2,089.82

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.