Home / 1,391.20-2,086.19-417.12

Finding the Fourth Proportional to 1,391.20, 2,086.19 and 417.12

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Solution

The fourth proportional to 1,391.20, 2,086.19 and 417.12 is: 625.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.20 : 2,086.19 = 417.12 : x
  2. Step 2: Convert to fraction form
    1,391.20/2,086.19 = 417.12/x
  3. Step 3: Cross multiply
    1,391.20x = 2,086.19 × 417.12
  4. Step 4: Simplify right side
    1,391.20x = 870,179.06
  5. Step 5: Solve for x
    x = 870,179.06/1,391.20
  6. Step 6: Final answer
    x = 625.49

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1.5x scale

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.