Home / 1,320.30-1,976.40-770.85

Finding the Fourth Proportional to 1,320.30, 1,976.40 and 770.85

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Solution

The fourth proportional to 1,320.30, 1,976.40 and 770.85 is: 1,153.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,320.30 : 1,976.40 = 770.85 : x
  2. Step 2: Convert to fraction form
    1,320.30/1,976.40 = 770.85/x
  3. Step 3: Cross multiply
    1,320.30x = 1,976.40 × 770.85
  4. Step 4: Simplify right side
    1,320.30x = 1,523,507.94
  5. Step 5: Solve for x
    x = 1,523,507.94/1,320.30
  6. Step 6: Final answer
    x = 1,153.91

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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.