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Finding the Fourth Proportional to 86.76, 119.72 and 65.02

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Solution

The fourth proportional to 86.76, 119.72 and 65.02 is: 89.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.76 : 119.72 = 65.02 : x
  2. Step 2: Convert to fraction form
    86.76/119.72 = 65.02/x
  3. Step 3: Cross multiply
    86.76x = 119.72 × 65.02
  4. Step 4: Simplify right side
    86.76x = 7,784.19
  5. Step 5: Solve for x
    x = 7,784.19/86.76
  6. Step 6: Final answer
    x = 89.72

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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.