Home / 1,278.72-1,918.12-498.90

Finding the Fourth Proportional to 1,278.72, 1,918.12 and 498.90

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Solution

The fourth proportional to 1,278.72, 1,918.12 and 498.90 is: 748.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.72 : 1,918.12 = 498.90 : x
  2. Step 2: Convert to fraction form
    1,278.72/1,918.12 = 498.90/x
  3. Step 3: Cross multiply
    1,278.72x = 1,918.12 × 498.90
  4. Step 4: Simplify right side
    1,278.72x = 956,952.96
  5. Step 5: Solve for x
    x = 956,952.96/1,278.72
  6. Step 6: Final answer
    x = 748.37

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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.