Home / 1,320.80-1,981.50-499.08

Finding the Fourth Proportional to 1,320.80, 1,981.50 and 499.08

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Solution

The fourth proportional to 1,320.80, 1,981.50 and 499.08 is: 748.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,320.80 : 1,981.50 = 499.08 : x
  2. Step 2: Convert to fraction form
    1,320.80/1,981.50 = 499.08/x
  3. Step 3: Cross multiply
    1,320.80x = 1,981.50 × 499.08
  4. Step 4: Simplify right side
    1,320.80x = 988,927.02
  5. Step 5: Solve for x
    x = 988,927.02/1,320.80
  6. Step 6: Final answer
    x = 748.73

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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.