Home / 1,290.41-1,935.61-520.91

Finding the Fourth Proportional to 1,290.41, 1,935.61 and 520.91

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Solution

The fourth proportional to 1,290.41, 1,935.61 and 520.91 is: 781.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.41 : 1,935.61 = 520.91 : x
  2. Step 2: Convert to fraction form
    1,290.41/1,935.61 = 520.91/x
  3. Step 3: Cross multiply
    1,290.41x = 1,935.61 × 520.91
  4. Step 4: Simplify right side
    1,290.41x = 1,008,278.61
  5. Step 5: Solve for x
    x = 1,008,278.61/1,290.41
  6. Step 6: Final answer
    x = 781.36

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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.