Home / 1,120.30-1,680.45-828.70

Finding the Fourth Proportional to 1,120.30, 1,680.45 and 828.70

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Solution

The fourth proportional to 1,120.30, 1,680.45 and 828.70 is: 1,243.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,120.30 : 1,680.45 = 828.70 : x
  2. Step 2: Convert to fraction form
    1,120.30/1,680.45 = 828.70/x
  3. Step 3: Cross multiply
    1,120.30x = 1,680.45 × 828.70
  4. Step 4: Simplify right side
    1,120.30x = 1,392,588.92
  5. Step 5: Solve for x
    x = 1,392,588.92/1,120.30
  6. Step 6: Final answer
    x = 1,243.05

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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.