Home / 1,439.58-2,157.28-780.90

Finding the Fourth Proportional to 1,439.58, 2,157.28 and 780.90

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Solution

The fourth proportional to 1,439.58, 2,157.28 and 780.90 is: 1,170.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,439.58 : 2,157.28 = 780.90 : x
  2. Step 2: Convert to fraction form
    1,439.58/2,157.28 = 780.90/x
  3. Step 3: Cross multiply
    1,439.58x = 2,157.28 × 780.90
  4. Step 4: Simplify right side
    1,439.58x = 1,684,619.95
  5. Step 5: Solve for x
    x = 1,684,619.95/1,439.58
  6. Step 6: Final answer
    x = 1,170.22

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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.