Home / 1,390.11-2,086.20-659.70

Finding the Fourth Proportional to 1,390.11, 2,086.20 and 659.70

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Solution

The fourth proportional to 1,390.11, 2,086.20 and 659.70 is: 990.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.11 : 2,086.20 = 659.70 : x
  2. Step 2: Convert to fraction form
    1,390.11/2,086.20 = 659.70/x
  3. Step 3: Cross multiply
    1,390.11x = 2,086.20 × 659.70
  4. Step 4: Simplify right side
    1,390.11x = 1,376,266.14
  5. Step 5: Solve for x
    x = 1,376,266.14/1,390.11
  6. Step 6: Final answer
    x = 990.04

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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.