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Finding the Fourth Proportional to 285.40, 428.16 and 155.53

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Solution

The fourth proportional to 285.40, 428.16 and 155.53 is: 233.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.40 : 428.16 = 155.53 : x
  2. Step 2: Convert to fraction form
    285.40/428.16 = 155.53/x
  3. Step 3: Cross multiply
    285.40x = 428.16 × 155.53
  4. Step 4: Simplify right side
    285.40x = 66,589.58
  5. Step 5: Solve for x
    x = 66,589.58/285.40
  6. Step 6: Final answer
    x = 233.32

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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.