Home / 1,313.60-1,969.40-664.80

Finding the Fourth Proportional to 1,313.60, 1,969.40 and 664.80

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Solution

The fourth proportional to 1,313.60, 1,969.40 and 664.80 is: 996.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,313.60 : 1,969.40 = 664.80 : x
  2. Step 2: Convert to fraction form
    1,313.60/1,969.40 = 664.80/x
  3. Step 3: Cross multiply
    1,313.60x = 1,969.40 × 664.80
  4. Step 4: Simplify right side
    1,313.60x = 1,309,257.12
  5. Step 5: Solve for x
    x = 1,309,257.12/1,313.60
  6. Step 6: Final answer
    x = 996.69

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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.