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Finding the Fourth Proportional to 78.34, 117.08 and 57.88

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Solution

The fourth proportional to 78.34, 117.08 and 57.88 is: 86.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.34 : 117.08 = 57.88 : x
  2. Step 2: Convert to fraction form
    78.34/117.08 = 57.88/x
  3. Step 3: Cross multiply
    78.34x = 117.08 × 57.88
  4. Step 4: Simplify right side
    78.34x = 6,776.59
  5. Step 5: Solve for x
    x = 6,776.59/78.34
  6. Step 6: Final answer
    x = 86.50

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.