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Finding the Fourth Proportional to 512.75, 707.65 and 288.72

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Solution

The fourth proportional to 512.75, 707.65 and 288.72 is: 398.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.75 : 707.65 = 288.72 : x
  2. Step 2: Convert to fraction form
    512.75/707.65 = 288.72/x
  3. Step 3: Cross multiply
    512.75x = 707.65 × 288.72
  4. Step 4: Simplify right side
    512.75x = 204,311.99
  5. Step 5: Solve for x
    x = 204,311.99/512.75
  6. Step 6: Final answer
    x = 398.46

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Find fourth proportional to 256.38, 353.82 and 144.36
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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.