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Finding the Fourth Proportional to 51.42, 71.04 and 39.81

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Solution

The fourth proportional to 51.42, 71.04 and 39.81 is: 55.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.42 : 71.04 = 39.81 : x
  2. Step 2: Convert to fraction form
    51.42/71.04 = 39.81/x
  3. Step 3: Cross multiply
    51.42x = 71.04 × 39.81
  4. Step 4: Simplify right side
    51.42x = 2,827.90
  5. Step 5: Solve for x
    x = 2,827.90/51.42
  6. Step 6: Final answer
    x = 55.00

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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.