Home / 1,040.39-1,560.30-309.80

Finding the Fourth Proportional to 1,040.39, 1,560.30 and 309.80

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Solution

The fourth proportional to 1,040.39, 1,560.30 and 309.80 is: 464.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,040.39 : 1,560.30 = 309.80 : x
  2. Step 2: Convert to fraction form
    1,040.39/1,560.30 = 309.80/x
  3. Step 3: Cross multiply
    1,040.39x = 1,560.30 × 309.80
  4. Step 4: Simplify right side
    1,040.39x = 483,373.14
  5. Step 5: Solve for x
    x = 483,373.14/1,040.39
  6. Step 6: Final answer
    x = 464.61

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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.