Home / 1,279.78-1,766.13-720.36

Finding the Fourth Proportional to 1,279.78, 1,766.13 and 720.36

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Solution

The fourth proportional to 1,279.78, 1,766.13 and 720.36 is: 994.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.78 : 1,766.13 = 720.36 : x
  2. Step 2: Convert to fraction form
    1,279.78/1,766.13 = 720.36/x
  3. Step 3: Cross multiply
    1,279.78x = 1,766.13 × 720.36
  4. Step 4: Simplify right side
    1,279.78x = 1,272,249.41
  5. Step 5: Solve for x
    x = 1,272,249.41/1,279.78
  6. Step 6: Final answer
    x = 994.12

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.