Home / 1,318.40-1,819.33-720.88

Finding the Fourth Proportional to 1,318.40, 1,819.33 and 720.88

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Solution

The fourth proportional to 1,318.40, 1,819.33 and 720.88 is: 994.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,318.40 : 1,819.33 = 720.88 : x
  2. Step 2: Convert to fraction form
    1,318.40/1,819.33 = 720.88/x
  3. Step 3: Cross multiply
    1,318.40x = 1,819.33 × 720.88
  4. Step 4: Simplify right side
    1,318.40x = 1,311,509.99
  5. Step 5: Solve for x
    x = 1,311,509.99/1,318.40
  6. Step 6: Final answer
    x = 994.78

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.