Home / 1,215.30-1,813.64-939.90

Finding the Fourth Proportional to 1,215.30, 1,813.64 and 939.90

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Solution

The fourth proportional to 1,215.30, 1,813.64 and 939.90 is: 1,402.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,215.30 : 1,813.64 = 939.90 : x
  2. Step 2: Convert to fraction form
    1,215.30/1,813.64 = 939.90/x
  3. Step 3: Cross multiply
    1,215.30x = 1,813.64 × 939.90
  4. Step 4: Simplify right side
    1,215.30x = 1,704,640.24
  5. Step 5: Solve for x
    x = 1,704,640.24/1,215.30
  6. Step 6: Final answer
    x = 1,402.65

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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.