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Finding the Fourth Proportional to 342.50, 513.60 and 212.50

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Solution

The fourth proportional to 342.50, 513.60 and 212.50 is: 318.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.50 : 513.60 = 212.50 : x
  2. Step 2: Convert to fraction form
    342.50/513.60 = 212.50/x
  3. Step 3: Cross multiply
    342.50x = 513.60 × 212.50
  4. Step 4: Simplify right side
    342.50x = 109,140.28
  5. Step 5: Solve for x
    x = 109,140.28/342.50
  6. Step 6: Final answer
    x = 318.65

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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.