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Finding the Fourth Proportional to 158.03, 218.05 and 90.72

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Solution

The fourth proportional to 158.03, 218.05 and 90.72 is: 125.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    158.03 : 218.05 = 90.72 : x
  2. Step 2: Convert to fraction form
    158.03/218.05 = 90.72/x
  3. Step 3: Cross multiply
    158.03x = 218.05 × 90.72
  4. Step 4: Simplify right side
    158.03x = 19,781.50
  5. Step 5: Solve for x
    x = 19,781.50/158.03
  6. Step 6: Final answer
    x = 125.18

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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.