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Finding the Fourth Proportional to 65.85, 99.15 and 61.80

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Solution

The fourth proportional to 65.85, 99.15 and 61.80 is: 93.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.85 : 99.15 = 61.80 : x
  2. Step 2: Convert to fraction form
    65.85/99.15 = 61.80/x
  3. Step 3: Cross multiply
    65.85x = 99.15 × 61.80
  4. Step 4: Simplify right side
    65.85x = 6,127.47
  5. Step 5: Solve for x
    x = 6,127.47/65.85
  6. Step 6: Final answer
    x = 93.05

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.