Home / 1,387.12-2,071.68-1,256.86

Finding the Fourth Proportional to 1,387.12, 2,071.68 and 1,256.86

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Solution

The fourth proportional to 1,387.12, 2,071.68 and 1,256.86 is: 1,877.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.12 : 2,071.68 = 1,256.86 : x
  2. Step 2: Convert to fraction form
    1,387.12/2,071.68 = 1,256.86/x
  3. Step 3: Cross multiply
    1,387.12x = 2,071.68 × 1,256.86
  4. Step 4: Simplify right side
    1,387.12x = 2,603,811.72
  5. Step 5: Solve for x
    x = 2,603,811.72/1,387.12
  6. Step 6: Final answer
    x = 1,877.14

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.