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Finding the Fourth Proportional to 387.46, 534.70 and 212.80

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Solution

The fourth proportional to 387.46, 534.70 and 212.80 is: 293.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.46 : 534.70 = 212.80 : x
  2. Step 2: Convert to fraction form
    387.46/534.70 = 212.80/x
  3. Step 3: Cross multiply
    387.46x = 534.70 × 212.80
  4. Step 4: Simplify right side
    387.46x = 113,784.16
  5. Step 5: Solve for x
    x = 113,784.16/387.46
  6. Step 6: Final answer
    x = 293.67

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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.