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Finding the Fourth Proportional to 98.12, 147.80 and 78.08

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Solution

The fourth proportional to 98.12, 147.80 and 78.08 is: 117.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    98.12 : 147.80 = 78.08 : x
  2. Step 2: Convert to fraction form
    98.12/147.80 = 78.08/x
  3. Step 3: Cross multiply
    98.12x = 147.80 × 78.08
  4. Step 4: Simplify right side
    98.12x = 11,540.22
  5. Step 5: Solve for x
    x = 11,540.22/98.12
  6. Step 6: Final answer
    x = 117.61

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.