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Finding the Fourth Proportional to 55.68, 76.80 and 51.68

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Solution

The fourth proportional to 55.68, 76.80 and 51.68 is: 71.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.68 : 76.80 = 51.68 : x
  2. Step 2: Convert to fraction form
    55.68/76.80 = 51.68/x
  3. Step 3: Cross multiply
    55.68x = 76.80 × 51.68
  4. Step 4: Simplify right side
    55.68x = 3,969.02
  5. Step 5: Solve for x
    x = 3,969.02/55.68
  6. Step 6: Final answer
    x = 71.28

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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.