Home / 1,278.81-1,918.25-498.78

Finding the Fourth Proportional to 1,278.81, 1,918.25 and 498.78

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Solution

The fourth proportional to 1,278.81, 1,918.25 and 498.78 is: 748.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.81 : 1,918.25 = 498.78 : x
  2. Step 2: Convert to fraction form
    1,278.81/1,918.25 = 498.78/x
  3. Step 3: Cross multiply
    1,278.81x = 1,918.25 × 498.78
  4. Step 4: Simplify right side
    1,278.81x = 956,786.92
  5. Step 5: Solve for x
    x = 956,786.92/1,278.81
  6. Step 6: Final answer
    x = 748.19

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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.