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Finding the Fourth Proportional to 316.50, 436.86 and 279.78

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Solution

The fourth proportional to 316.50, 436.86 and 279.78 is: 386.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    316.50 : 436.86 = 279.78 : x
  2. Step 2: Convert to fraction form
    316.50/436.86 = 279.78/x
  3. Step 3: Cross multiply
    316.50x = 436.86 × 279.78
  4. Step 4: Simplify right side
    316.50x = 122,224.69
  5. Step 5: Solve for x
    x = 122,224.69/316.50
  6. Step 6: Final answer
    x = 386.18

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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.