Home / 1,224.20-1,689.36-664.66

Finding the Fourth Proportional to 1,224.20, 1,689.36 and 664.66

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Solution

The fourth proportional to 1,224.20, 1,689.36 and 664.66 is: 917.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,224.20 : 1,689.36 = 664.66 : x
  2. Step 2: Convert to fraction form
    1,224.20/1,689.36 = 664.66/x
  3. Step 3: Cross multiply
    1,224.20x = 1,689.36 × 664.66
  4. Step 4: Simplify right side
    1,224.20x = 1,122,851.08
  5. Step 5: Solve for x
    x = 1,122,851.08/1,224.20
  6. Step 6: Final answer
    x = 917.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.