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Finding the Fourth Proportional to 88.28, 121.68 and 71.88

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Solution

The fourth proportional to 88.28, 121.68 and 71.88 is: 99.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.28 : 121.68 = 71.88 : x
  2. Step 2: Convert to fraction form
    88.28/121.68 = 71.88/x
  3. Step 3: Cross multiply
    88.28x = 121.68 × 71.88
  4. Step 4: Simplify right side
    88.28x = 8,746.36
  5. Step 5: Solve for x
    x = 8,746.36/88.28
  6. Step 6: Final answer
    x = 99.08

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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.