Home / 2,155.40-3,230.76-921.80

Finding the Fourth Proportional to 2,155.40, 3,230.76 and 921.80

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Solution

The fourth proportional to 2,155.40, 3,230.76 and 921.80 is: 1,381.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,155.40 : 3,230.76 = 921.80 : x
  2. Step 2: Convert to fraction form
    2,155.40/3,230.76 = 921.80/x
  3. Step 3: Cross multiply
    2,155.40x = 3,230.76 × 921.80
  4. Step 4: Simplify right side
    2,155.40x = 2,978,114.57
  5. Step 5: Solve for x
    x = 2,978,114.57/2,155.40
  6. Step 6: Final answer
    x = 1,381.70

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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.