Home / 1,821.07-2,731.60-780.40

Finding the Fourth Proportional to 1,821.07, 2,731.60 and 780.40

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Solution

The fourth proportional to 1,821.07, 2,731.60 and 780.40 is: 1,170.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,821.07 : 2,731.60 = 780.40 : x
  2. Step 2: Convert to fraction form
    1,821.07/2,731.60 = 780.40/x
  3. Step 3: Cross multiply
    1,821.07x = 2,731.60 × 780.40
  4. Step 4: Simplify right side
    1,821.07x = 2,131,726.98
  5. Step 5: Solve for x
    x = 2,131,726.98/1,821.07
  6. Step 6: Final answer
    x = 1,170.59

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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.