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Finding the Fourth Proportional to 55.90, 76.80 and 49.75

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Solution

The fourth proportional to 55.90, 76.80 and 49.75 is: 68.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.90 : 76.80 = 49.75 : x
  2. Step 2: Convert to fraction form
    55.90/76.80 = 49.75/x
  3. Step 3: Cross multiply
    55.90x = 76.80 × 49.75
  4. Step 4: Simplify right side
    55.90x = 3,820.80
  5. Step 5: Solve for x
    x = 3,820.80/55.90
  6. Step 6: Final answer
    x = 68.35

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.