Home / 1,417.20-2,123.65-685.90

Finding the Fourth Proportional to 1,417.20, 2,123.65 and 685.90

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Solution

The fourth proportional to 1,417.20, 2,123.65 and 685.90 is: 1,027.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,417.20 : 2,123.65 = 685.90 : x
  2. Step 2: Convert to fraction form
    1,417.20/2,123.65 = 685.90/x
  3. Step 3: Cross multiply
    1,417.20x = 2,123.65 × 685.90
  4. Step 4: Simplify right side
    1,417.20x = 1,456,611.54
  5. Step 5: Solve for x
    x = 1,456,611.54/1,417.20
  6. Step 6: Final answer
    x = 1,027.81

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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.