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Finding the Fourth Proportional to 538.99, 808.78 and 209.95

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Solution

The fourth proportional to 538.99, 808.78 and 209.95 is: 315.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.99 : 808.78 = 209.95 : x
  2. Step 2: Convert to fraction form
    538.99/808.78 = 209.95/x
  3. Step 3: Cross multiply
    538.99x = 808.78 × 209.95
  4. Step 4: Simplify right side
    538.99x = 169,803.36
  5. Step 5: Solve for x
    x = 169,803.36/538.99
  6. Step 6: Final answer
    x = 315.04

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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.