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Finding the Fourth Proportional to 253.55, 380.33 and 212.90

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Solution

The fourth proportional to 253.55, 380.33 and 212.90 is: 319.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.55 : 380.33 = 212.90 : x
  2. Step 2: Convert to fraction form
    253.55/380.33 = 212.90/x
  3. Step 3: Cross multiply
    253.55x = 380.33 × 212.90
  4. Step 4: Simplify right side
    253.55x = 80,971.19
  5. Step 5: Solve for x
    x = 80,971.19/253.55
  6. Step 6: Final answer
    x = 319.35

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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.