Home / 1,291.80-1,937.70-1,270.20

Finding the Fourth Proportional to 1,291.80, 1,937.70 and 1,270.20

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Solution

The fourth proportional to 1,291.80, 1,937.70 and 1,270.20 is: 1,905.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,291.80 : 1,937.70 = 1,270.20 : x
  2. Step 2: Convert to fraction form
    1,291.80/1,937.70 = 1,270.20/x
  3. Step 3: Cross multiply
    1,291.80x = 1,937.70 × 1,270.20
  4. Step 4: Simplify right side
    1,291.80x = 2,461,266.54
  5. Step 5: Solve for x
    x = 2,461,266.54/1,291.80
  6. Step 6: Final answer
    x = 1,905.30

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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.