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Finding the Fourth Proportional to 65.51, 90.41 and 39.31

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Solution

The fourth proportional to 65.51, 90.41 and 39.31 is: 54.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.51 : 90.41 = 39.31 : x
  2. Step 2: Convert to fraction form
    65.51/90.41 = 39.31/x
  3. Step 3: Cross multiply
    65.51x = 90.41 × 39.31
  4. Step 4: Simplify right side
    65.51x = 3,554.02
  5. Step 5: Solve for x
    x = 3,554.02/65.51
  6. Step 6: Final answer
    x = 54.25

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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.