Home / 1,128.40-1,690.20-614.80

Finding the Fourth Proportional to 1,128.40, 1,690.20 and 614.80

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Solution

The fourth proportional to 1,128.40, 1,690.20 and 614.80 is: 920.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,128.40 : 1,690.20 = 614.80 : x
  2. Step 2: Convert to fraction form
    1,128.40/1,690.20 = 614.80/x
  3. Step 3: Cross multiply
    1,128.40x = 1,690.20 × 614.80
  4. Step 4: Simplify right side
    1,128.40x = 1,039,134.96
  5. Step 5: Solve for x
    x = 1,039,134.96/1,128.40
  6. Step 6: Final answer
    x = 920.89

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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.