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Finding the Fourth Proportional to 74.09, 101.70 and 65.72

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Solution

The fourth proportional to 74.09, 101.70 and 65.72 is: 90.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    74.09 : 101.70 = 65.72 : x
  2. Step 2: Convert to fraction form
    74.09/101.70 = 65.72/x
  3. Step 3: Cross multiply
    74.09x = 101.70 × 65.72
  4. Step 4: Simplify right side
    74.09x = 6,683.72
  5. Step 5: Solve for x
    x = 6,683.72/74.09
  6. Step 6: Final answer
    x = 90.21

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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.