Home / 1,419.12-2,129.28-769.80

Finding the Fourth Proportional to 1,419.12, 2,129.28 and 769.80

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Solution

The fourth proportional to 1,419.12, 2,129.28 and 769.80 is: 1,155.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,419.12 : 2,129.28 = 769.80 : x
  2. Step 2: Convert to fraction form
    1,419.12/2,129.28 = 769.80/x
  3. Step 3: Cross multiply
    1,419.12x = 2,129.28 × 769.80
  4. Step 4: Simplify right side
    1,419.12x = 1,639,119.74
  5. Step 5: Solve for x
    x = 1,639,119.74/1,419.12
  6. Step 6: Final answer
    x = 1,155.03

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1.5x scale

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.