Home / 1,320.80-1,981.12-455.04

Finding the Fourth Proportional to 1,320.80, 1,981.12 and 455.04

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Solution

The fourth proportional to 1,320.80, 1,981.12 and 455.04 is: 682.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,320.80 : 1,981.12 = 455.04 : x
  2. Step 2: Convert to fraction form
    1,320.80/1,981.12 = 455.04/x
  3. Step 3: Cross multiply
    1,320.80x = 1,981.12 × 455.04
  4. Step 4: Simplify right side
    1,320.80x = 901,488.84
  5. Step 5: Solve for x
    x = 901,488.84/1,320.80
  6. Step 6: Final answer
    x = 682.53

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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.