Home / 1,230.40-1,840.20-938.80

Finding the Fourth Proportional to 1,230.40, 1,840.20 and 938.80

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Solution

The fourth proportional to 1,230.40, 1,840.20 and 938.80 is: 1,404.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,230.40 : 1,840.20 = 938.80 : x
  2. Step 2: Convert to fraction form
    1,230.40/1,840.20 = 938.80/x
  3. Step 3: Cross multiply
    1,230.40x = 1,840.20 × 938.80
  4. Step 4: Simplify right side
    1,230.40x = 1,727,579.76
  5. Step 5: Solve for x
    x = 1,727,579.76/1,230.40
  6. Step 6: Final answer
    x = 1,404.08

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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.