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Finding the Fourth Proportional to 285.40, 427.80 and 220.18

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Solution

The fourth proportional to 285.40, 427.80 and 220.18 is: 330.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.40 : 427.80 = 220.18 : x
  2. Step 2: Convert to fraction form
    285.40/427.80 = 220.18/x
  3. Step 3: Cross multiply
    285.40x = 427.80 × 220.18
  4. Step 4: Simplify right side
    285.40x = 94,193.00
  5. Step 5: Solve for x
    x = 94,193.00/285.40
  6. Step 6: Final answer
    x = 330.04

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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.