Home / 8,139.79-12,209.70-3,980.14

Finding the Fourth Proportional to 8,139.79, 12,209.70 and 3,980.14

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Solution

The fourth proportional to 8,139.79, 12,209.70 and 3,980.14 is: 5,970.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    8,139.79 : 12,209.70 = 3,980.14 : x
  2. Step 2: Convert to fraction form
    8,139.79/12,209.70 = 3,980.14/x
  3. Step 3: Cross multiply
    8,139.79x = 12,209.70 × 3,980.14
  4. Step 4: Simplify right side
    8,139.79x = 48,596,299.76
  5. Step 5: Solve for x
    x = 48,596,299.76/8,139.79
  6. Step 6: Final answer
    x = 5,970.21

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Double scale
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Similar ratio
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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.