Home / 3,897.15-5,378.09-2,128.80

Finding the Fourth Proportional to 3,897.15, 5,378.09 and 2,128.80

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Solution

The fourth proportional to 3,897.15, 5,378.09 and 2,128.80 is: 2,937.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,897.15 : 5,378.09 = 2,128.80 : x
  2. Step 2: Convert to fraction form
    3,897.15/5,378.09 = 2,128.80/x
  3. Step 3: Cross multiply
    3,897.15x = 5,378.09 × 2,128.80
  4. Step 4: Simplify right side
    3,897.15x = 11,448,877.99
  5. Step 5: Solve for x
    x = 11,448,877.99/3,897.15
  6. Step 6: Final answer
    x = 2,937.76

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.