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Finding the Fourth Proportional to 225, 310.50 and 121.50

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Solution

The fourth proportional to 225, 310.50 and 121.50 is: 167.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    225 : 310.50 = 121.50 : x
  2. Step 2: Convert to fraction form
    225/310.50 = 121.50/x
  3. Step 3: Cross multiply
    225x = 310.50 × 121.50
  4. Step 4: Simplify right side
    225x = 37,725.75
  5. Step 5: Solve for x
    x = 37,725.75/225
  6. Step 6: Final answer
    x = 167.67

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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.