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Finding the Fourth Proportional to 85.04, 126.64 and 78.08

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Solution

The fourth proportional to 85.04, 126.64 and 78.08 is: 116.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.04 : 126.64 = 78.08 : x
  2. Step 2: Convert to fraction form
    85.04/126.64 = 78.08/x
  3. Step 3: Cross multiply
    85.04x = 126.64 × 78.08
  4. Step 4: Simplify right side
    85.04x = 9,888.05
  5. Step 5: Solve for x
    x = 9,888.05/85.04
  6. Step 6: Final answer
    x = 116.28

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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.