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Finding the Fourth Proportional to 78.08, 116.80 and 76.16

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Solution

The fourth proportional to 78.08, 116.80 and 76.16 is: 113.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.08 : 116.80 = 76.16 : x
  2. Step 2: Convert to fraction form
    78.08/116.80 = 76.16/x
  3. Step 3: Cross multiply
    78.08x = 116.80 × 76.16
  4. Step 4: Simplify right side
    78.08x = 8,895.49
  5. Step 5: Solve for x
    x = 8,895.49/78.08
  6. Step 6: Final answer
    x = 113.93

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.