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Finding the Fourth Proportional to 171.51, 256.80 and 90.18

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Solution

The fourth proportional to 171.51, 256.80 and 90.18 is: 135.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.51 : 256.80 = 90.18 : x
  2. Step 2: Convert to fraction form
    171.51/256.80 = 90.18/x
  3. Step 3: Cross multiply
    171.51x = 256.80 × 90.18
  4. Step 4: Simplify right side
    171.51x = 23,158.22
  5. Step 5: Solve for x
    x = 23,158.22/171.51
  6. Step 6: Final answer
    x = 135.03

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.