Home / 2,820.40-3,891.80-1,561.28

Finding the Fourth Proportional to 2,820.40, 3,891.80 and 1,561.28

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Solution

The fourth proportional to 2,820.40, 3,891.80 and 1,561.28 is: 2,154.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,820.40 : 3,891.80 = 1,561.28 : x
  2. Step 2: Convert to fraction form
    2,820.40/3,891.80 = 1,561.28/x
  3. Step 3: Cross multiply
    2,820.40x = 3,891.80 × 1,561.28
  4. Step 4: Simplify right side
    2,820.40x = 6,076,189.50
  5. Step 5: Solve for x
    x = 6,076,189.50/2,820.40
  6. Step 6: Final answer
    x = 2,154.37

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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.