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Finding the Fourth Proportional to 86.04, 128.70 and 65.52

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Solution

The fourth proportional to 86.04, 128.70 and 65.52 is: 98.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.04 : 128.70 = 65.52 : x
  2. Step 2: Convert to fraction form
    86.04/128.70 = 65.52/x
  3. Step 3: Cross multiply
    86.04x = 128.70 × 65.52
  4. Step 4: Simplify right side
    86.04x = 8,432.42
  5. Step 5: Solve for x
    x = 8,432.42/86.04
  6. Step 6: Final answer
    x = 98.01

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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.