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Finding the Fourth Proportional to 498.06, 685.80 and 399.42

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Solution

The fourth proportional to 498.06, 685.80 and 399.42 is: 549.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.06 : 685.80 = 399.42 : x
  2. Step 2: Convert to fraction form
    498.06/685.80 = 399.42/x
  3. Step 3: Cross multiply
    498.06x = 685.80 × 399.42
  4. Step 4: Simplify right side
    498.06x = 273,922.24
  5. Step 5: Solve for x
    x = 273,922.24/498.06
  6. Step 6: Final answer
    x = 549.98

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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.