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Finding the Fourth Proportional to 79.84, 109.98 and 71.98

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Solution

The fourth proportional to 79.84, 109.98 and 71.98 is: 99.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.84 : 109.98 = 71.98 : x
  2. Step 2: Convert to fraction form
    79.84/109.98 = 71.98/x
  3. Step 3: Cross multiply
    79.84x = 109.98 × 71.98
  4. Step 4: Simplify right side
    79.84x = 7,916.36
  5. Step 5: Solve for x
    x = 7,916.36/79.84
  6. Step 6: Final answer
    x = 99.15

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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.