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Finding the Fourth Proportional to 88.12, 121.28 and 64.77

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Solution

The fourth proportional to 88.12, 121.28 and 64.77 is: 89.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.12 : 121.28 = 64.77 : x
  2. Step 2: Convert to fraction form
    88.12/121.28 = 64.77/x
  3. Step 3: Cross multiply
    88.12x = 121.28 × 64.77
  4. Step 4: Simplify right side
    88.12x = 7,854.62
  5. Step 5: Solve for x
    x = 7,854.62/88.12
  6. Step 6: Final answer
    x = 89.14

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Find fourth proportional to 44.06, 60.64 and 32.38
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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.