Home / 1,309.91-1,965.20-385.47

Finding the Fourth Proportional to 1,309.91, 1,965.20 and 385.47

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Solution

The fourth proportional to 1,309.91, 1,965.20 and 385.47 is: 578.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,309.91 : 1,965.20 = 385.47 : x
  2. Step 2: Convert to fraction form
    1,309.91/1,965.20 = 385.47/x
  3. Step 3: Cross multiply
    1,309.91x = 1,965.20 × 385.47
  4. Step 4: Simplify right side
    1,309.91x = 757,523.72
  5. Step 5: Solve for x
    x = 757,523.72/1,309.91
  6. Step 6: Final answer
    x = 578.30

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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.