Home / 1,391.36-2,086.80-417.20

Finding the Fourth Proportional to 1,391.36, 2,086.80 and 417.20

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Solution

The fourth proportional to 1,391.36, 2,086.80 and 417.20 is: 625.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.36 : 2,086.80 = 417.20 : x
  2. Step 2: Convert to fraction form
    1,391.36/2,086.80 = 417.20/x
  3. Step 3: Cross multiply
    1,391.36x = 2,086.80 × 417.20
  4. Step 4: Simplify right side
    1,391.36x = 870,612.96
  5. Step 5: Solve for x
    x = 870,612.96/1,391.36
  6. Step 6: Final answer
    x = 625.73

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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.