Home / 1,421-2,127.40-1,272.80

Finding the Fourth Proportional to 1,421, 2,127.40 and 1,272.80

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Solution

The fourth proportional to 1,421, 2,127.40 and 1,272.80 is: 1,905.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421 : 2,127.40 = 1,272.80 : x
  2. Step 2: Convert to fraction form
    1,421/2,127.40 = 1,272.80/x
  3. Step 3: Cross multiply
    1,421x = 2,127.40 × 1,272.80
  4. Step 4: Simplify right side
    1,421x = 2,707,754.72
  5. Step 5: Solve for x
    x = 2,707,754.72/1,421
  6. Step 6: Final answer
    x = 1,905.53

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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.