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Finding the Fourth Proportional to 858.08, 1,287.12 and 208.82

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Solution

The fourth proportional to 858.08, 1,287.12 and 208.82 is: 313.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.08 : 1,287.12 = 208.82 : x
  2. Step 2: Convert to fraction form
    858.08/1,287.12 = 208.82/x
  3. Step 3: Cross multiply
    858.08x = 1,287.12 × 208.82
  4. Step 4: Simplify right side
    858.08x = 268,776.40
  5. Step 5: Solve for x
    x = 268,776.40/858.08
  6. Step 6: Final answer
    x = 313.23

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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.