Home / 1,387.80-2,087.15-1,207.35

Finding the Fourth Proportional to 1,387.80, 2,087.15 and 1,207.35

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Solution

The fourth proportional to 1,387.80, 2,087.15 and 1,207.35 is: 1,815.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.80 : 2,087.15 = 1,207.35 : x
  2. Step 2: Convert to fraction form
    1,387.80/2,087.15 = 1,207.35/x
  3. Step 3: Cross multiply
    1,387.80x = 2,087.15 × 1,207.35
  4. Step 4: Simplify right side
    1,387.80x = 2,519,914.52
  5. Step 5: Solve for x
    x = 2,519,914.52/1,387.80
  6. Step 6: Final answer
    x = 1,815.76

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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.