Home / 1,268.20-1,902.30-919.90

Finding the Fourth Proportional to 1,268.20, 1,902.30 and 919.90

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Solution

The fourth proportional to 1,268.20, 1,902.30 and 919.90 is: 1,379.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,268.20 : 1,902.30 = 919.90 : x
  2. Step 2: Convert to fraction form
    1,268.20/1,902.30 = 919.90/x
  3. Step 3: Cross multiply
    1,268.20x = 1,902.30 × 919.90
  4. Step 4: Simplify right side
    1,268.20x = 1,749,925.77
  5. Step 5: Solve for x
    x = 1,749,925.77/1,268.20
  6. Step 6: Final answer
    x = 1,379.85

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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.