Home / 1,285.80-1,927.53-668.78

Finding the Fourth Proportional to 1,285.80, 1,927.53 and 668.78

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Solution

The fourth proportional to 1,285.80, 1,927.53 and 668.78 is: 1,002.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.80 : 1,927.53 = 668.78 : x
  2. Step 2: Convert to fraction form
    1,285.80/1,927.53 = 668.78/x
  3. Step 3: Cross multiply
    1,285.80x = 1,927.53 × 668.78
  4. Step 4: Simplify right side
    1,285.80x = 1,289,091.10
  5. Step 5: Solve for x
    x = 1,289,091.10/1,285.80
  6. Step 6: Final answer
    x = 1,002.56

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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.