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Finding the Fourth Proportional to 808.65, 1,212.87 and 288.63

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Solution

The fourth proportional to 808.65, 1,212.87 and 288.63 is: 432.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.65 : 1,212.87 = 288.63 : x
  2. Step 2: Convert to fraction form
    808.65/1,212.87 = 288.63/x
  3. Step 3: Cross multiply
    808.65x = 1,212.87 × 288.63
  4. Step 4: Simplify right side
    808.65x = 350,070.67
  5. Step 5: Solve for x
    x = 350,070.67/808.65
  6. Step 6: Final answer
    x = 432.91

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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.