Home / 1,271.85-1,909.71-1,209.20

Finding the Fourth Proportional to 1,271.85, 1,909.71 and 1,209.20

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Solution

The fourth proportional to 1,271.85, 1,909.71 and 1,209.20 is: 1,815.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,271.85 : 1,909.71 = 1,209.20 : x
  2. Step 2: Convert to fraction form
    1,271.85/1,909.71 = 1,209.20/x
  3. Step 3: Cross multiply
    1,271.85x = 1,909.71 × 1,209.20
  4. Step 4: Simplify right side
    1,271.85x = 2,309,226.11
  5. Step 5: Solve for x
    x = 2,309,226.11/1,271.85
  6. Step 6: Final answer
    x = 1,815.64

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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.