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Finding the Fourth Proportional to 65.40, 90.35 and 49.06

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Solution

The fourth proportional to 65.40, 90.35 and 49.06 is: 67.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.40 : 90.35 = 49.06 : x
  2. Step 2: Convert to fraction form
    65.40/90.35 = 49.06/x
  3. Step 3: Cross multiply
    65.40x = 90.35 × 49.06
  4. Step 4: Simplify right side
    65.40x = 4,432.57
  5. Step 5: Solve for x
    x = 4,432.57/65.40
  6. Step 6: Final answer
    x = 67.78

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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.