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Finding the Fourth Proportional to 860.06, 1,290.09 and 210.80

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Solution

The fourth proportional to 860.06, 1,290.09 and 210.80 is: 316.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.06 : 1,290.09 = 210.80 : x
  2. Step 2: Convert to fraction form
    860.06/1,290.09 = 210.80/x
  3. Step 3: Cross multiply
    860.06x = 1,290.09 × 210.80
  4. Step 4: Simplify right side
    860.06x = 271,954.99
  5. Step 5: Solve for x
    x = 271,954.99/860.06
  6. Step 6: Final answer
    x = 316.20

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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.