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Finding the Fourth Proportional to 860, 1,290 and 252

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Solution

The fourth proportional to 860, 1,290 and 252 is: 378

Step by Step Solution

  1. Step 1: Write the proportion equation
    860 : 1,290 = 252 : x
  2. Step 2: Convert to fraction form
    860/1,290 = 252/x
  3. Step 3: Cross multiply
    860x = 1,290 × 252
  4. Step 4: Simplify right side
    860x = 325,080
  5. Step 5: Solve for x
    x = 325,080/860
  6. Step 6: Final answer
    x = 378

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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.