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Finding the Fourth Proportional to 772.80, 1,159 and 279.16

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Solution

The fourth proportional to 772.80, 1,159 and 279.16 is: 418.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    772.80 : 1,159 = 279.16 : x
  2. Step 2: Convert to fraction form
    772.80/1,159 = 279.16/x
  3. Step 3: Cross multiply
    772.80x = 1,159 × 279.16
  4. Step 4: Simplify right side
    772.80x = 323,546.44
  5. Step 5: Solve for x
    x = 323,546.44/772.80
  6. Step 6: Final answer
    x = 418.67

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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.