Home / 1,121.24-1,682.61-428.49

Finding the Fourth Proportional to 1,121.24, 1,682.61 and 428.49

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Solution

The fourth proportional to 1,121.24, 1,682.61 and 428.49 is: 643.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,121.24 : 1,682.61 = 428.49 : x
  2. Step 2: Convert to fraction form
    1,121.24/1,682.61 = 428.49/x
  3. Step 3: Cross multiply
    1,121.24x = 1,682.61 × 428.49
  4. Step 4: Simplify right side
    1,121.24x = 720,979.95
  5. Step 5: Solve for x
    x = 720,979.95/1,121.24
  6. Step 6: Final answer
    x = 643.02

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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.