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Finding the Fourth Proportional to 218.60, 328.04 and 90.35

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Solution

The fourth proportional to 218.60, 328.04 and 90.35 is: 135.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.60 : 328.04 = 90.35 : x
  2. Step 2: Convert to fraction form
    218.60/328.04 = 90.35/x
  3. Step 3: Cross multiply
    218.60x = 328.04 × 90.35
  4. Step 4: Simplify right side
    218.60x = 29,636.77
  5. Step 5: Solve for x
    x = 29,636.77/218.60
  6. Step 6: Final answer
    x = 135.58

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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.