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Finding the Fourth Proportional to 252.80, 379.20 and 70.20

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Solution

The fourth proportional to 252.80, 379.20 and 70.20 is: 105.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    252.80 : 379.20 = 70.20 : x
  2. Step 2: Convert to fraction form
    252.80/379.20 = 70.20/x
  3. Step 3: Cross multiply
    252.80x = 379.20 × 70.20
  4. Step 4: Simplify right side
    252.80x = 26,619.71
  5. Step 5: Solve for x
    x = 26,619.71/252.80
  6. Step 6: Final answer
    x = 105.30

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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.