Home / 1,270.20-1,904.40-489.90

Finding the Fourth Proportional to 1,270.20, 1,904.40 and 489.90

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Solution

The fourth proportional to 1,270.20, 1,904.40 and 489.90 is: 734.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,270.20 : 1,904.40 = 489.90 : x
  2. Step 2: Convert to fraction form
    1,270.20/1,904.40 = 489.90/x
  3. Step 3: Cross multiply
    1,270.20x = 1,904.40 × 489.90
  4. Step 4: Simplify right side
    1,270.20x = 932,965.56
  5. Step 5: Solve for x
    x = 932,965.56/1,270.20
  6. Step 6: Final answer
    x = 734.50

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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.