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Finding the Fourth Proportional to 859.31, 1,288.95 and 210.05

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Solution

The fourth proportional to 859.31, 1,288.95 and 210.05 is: 315.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    859.31 : 1,288.95 = 210.05 : x
  2. Step 2: Convert to fraction form
    859.31/1,288.95 = 210.05/x
  3. Step 3: Cross multiply
    859.31x = 1,288.95 × 210.05
  4. Step 4: Simplify right side
    859.31x = 270,743.95
  5. Step 5: Solve for x
    x = 270,743.95/859.31
  6. Step 6: Final answer
    x = 315.07

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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.