Home / 2,145.80-3,218.70-1,321.40

Finding the Fourth Proportional to 2,145.80, 3,218.70 and 1,321.40

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Solution

The fourth proportional to 2,145.80, 3,218.70 and 1,321.40 is: 1,982.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,145.80 : 3,218.70 = 1,321.40 : x
  2. Step 2: Convert to fraction form
    2,145.80/3,218.70 = 1,321.40/x
  3. Step 3: Cross multiply
    2,145.80x = 3,218.70 × 1,321.40
  4. Step 4: Simplify right side
    2,145.80x = 4,253,190.18
  5. Step 5: Solve for x
    x = 4,253,190.18/2,145.80
  6. Step 6: Final answer
    x = 1,982.10

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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.