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Finding the Fourth Proportional to 78.34, 108.08 and 45.15

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Solution

The fourth proportional to 78.34, 108.08 and 45.15 is: 62.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.34 : 108.08 = 45.15 : x
  2. Step 2: Convert to fraction form
    78.34/108.08 = 45.15/x
  3. Step 3: Cross multiply
    78.34x = 108.08 × 45.15
  4. Step 4: Simplify right side
    78.34x = 4,879.38
  5. Step 5: Solve for x
    x = 4,879.38/78.34
  6. Step 6: Final answer
    x = 62.28

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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.