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Finding the Fourth Proportional to 891.28, 1,230 and 498.22

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Solution

The fourth proportional to 891.28, 1,230 and 498.22 is: 687.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.28 : 1,230 = 498.22 : x
  2. Step 2: Convert to fraction form
    891.28/1,230 = 498.22/x
  3. Step 3: Cross multiply
    891.28x = 1,230 × 498.22
  4. Step 4: Simplify right side
    891.28x = 612,810.60
  5. Step 5: Solve for x
    x = 612,810.60/891.28
  6. Step 6: Final answer
    x = 687.56

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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.