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Finding the Fourth Proportional to 21,012, 31,518 and 8,700

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Solution

The fourth proportional to 21,012, 31,518 and 8,700 is: 13,050

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,012 : 31,518 = 8,700 : x
  2. Step 2: Convert to fraction form
    21,012/31,518 = 8,700/x
  3. Step 3: Cross multiply
    21,012x = 31,518 × 8,700
  4. Step 4: Simplify right side
    21,012x = 274,206,600
  5. Step 5: Solve for x
    x = 274,206,600/21,012
  6. Step 6: Final answer
    x = 13,050

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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.