Home / 1,286.18-1,775.60-990.80

Finding the Fourth Proportional to 1,286.18, 1,775.60 and 990.80

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Solution

The fourth proportional to 1,286.18, 1,775.60 and 990.80 is: 1,367.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.18 : 1,775.60 = 990.80 : x
  2. Step 2: Convert to fraction form
    1,286.18/1,775.60 = 990.80/x
  3. Step 3: Cross multiply
    1,286.18x = 1,775.60 × 990.80
  4. Step 4: Simplify right side
    1,286.18x = 1,759,264.48
  5. Step 5: Solve for x
    x = 1,759,264.48/1,286.18
  6. Step 6: Final answer
    x = 1,367.82

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.