Home / 1,328.12-1,989.30-839.96

Finding the Fourth Proportional to 1,328.12, 1,989.30 and 839.96

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Solution

The fourth proportional to 1,328.12, 1,989.30 and 839.96 is: 1,258.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,328.12 : 1,989.30 = 839.96 : x
  2. Step 2: Convert to fraction form
    1,328.12/1,989.30 = 839.96/x
  3. Step 3: Cross multiply
    1,328.12x = 1,989.30 × 839.96
  4. Step 4: Simplify right side
    1,328.12x = 1,670,932.43
  5. Step 5: Solve for x
    x = 1,670,932.43/1,328.12
  6. Step 6: Final answer
    x = 1,258.12

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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.