Home / 1,313.29-1,969.80-619.78

Finding the Fourth Proportional to 1,313.29, 1,969.80 and 619.78

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Solution

The fourth proportional to 1,313.29, 1,969.80 and 619.78 is: 929.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,313.29 : 1,969.80 = 619.78 : x
  2. Step 2: Convert to fraction form
    1,313.29/1,969.80 = 619.78/x
  3. Step 3: Cross multiply
    1,313.29x = 1,969.80 × 619.78
  4. Step 4: Simplify right side
    1,313.29x = 1,220,842.64
  5. Step 5: Solve for x
    x = 1,220,842.64/1,313.29
  6. Step 6: Final answer
    x = 929.61

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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.