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Finding the Fourth Proportional to 79.30, 118.99 and 65.78

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Solution

The fourth proportional to 79.30, 118.99 and 65.78 is: 98.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.30 : 118.99 = 65.78 : x
  2. Step 2: Convert to fraction form
    79.30/118.99 = 65.78/x
  3. Step 3: Cross multiply
    79.30x = 118.99 × 65.78
  4. Step 4: Simplify right side
    79.30x = 7,827.16
  5. Step 5: Solve for x
    x = 7,827.16/79.30
  6. Step 6: Final answer
    x = 98.70

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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.