Home / 1,236.20-1,853.80-485.60

Finding the Fourth Proportional to 1,236.20, 1,853.80 and 485.60

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Solution

The fourth proportional to 1,236.20, 1,853.80 and 485.60 is: 728.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,236.20 : 1,853.80 = 485.60 : x
  2. Step 2: Convert to fraction form
    1,236.20/1,853.80 = 485.60/x
  3. Step 3: Cross multiply
    1,236.20x = 1,853.80 × 485.60
  4. Step 4: Simplify right side
    1,236.20x = 900,205.28
  5. Step 5: Solve for x
    x = 900,205.28/1,236.20
  6. Step 6: Final answer
    x = 728.20

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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.