Home / 21,002.80-31,439.40-12,211.60

Finding the Fourth Proportional to 21,002.80, 31,439.40 and 12,211.60

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Solution

The fourth proportional to 21,002.80, 31,439.40 and 12,211.60 is: 18,279.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,002.80 : 31,439.40 = 12,211.60 : x
  2. Step 2: Convert to fraction form
    21,002.80/31,439.40 = 12,211.60/x
  3. Step 3: Cross multiply
    21,002.80x = 31,439.40 × 12,211.60
  4. Step 4: Simplify right side
    21,002.80x = 383,925,377.04
  5. Step 5: Solve for x
    x = 383,925,377.04/21,002.80
  6. Step 6: Final answer
    x = 18,279.72

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1.5x scale

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.