Home / 1,279.30-1,918.88-401.78

Finding the Fourth Proportional to 1,279.30, 1,918.88 and 401.78

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Solution

The fourth proportional to 1,279.30, 1,918.88 and 401.78 is: 602.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.30 : 1,918.88 = 401.78 : x
  2. Step 2: Convert to fraction form
    1,279.30/1,918.88 = 401.78/x
  3. Step 3: Cross multiply
    1,279.30x = 1,918.88 × 401.78
  4. Step 4: Simplify right side
    1,279.30x = 770,967.61
  5. Step 5: Solve for x
    x = 770,967.61/1,279.30
  6. Step 6: Final answer
    x = 602.65

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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.