Home / 1,278.78-1,918.19-457.10

Finding the Fourth Proportional to 1,278.78, 1,918.19 and 457.10

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Solution

The fourth proportional to 1,278.78, 1,918.19 and 457.10 is: 685.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.78 : 1,918.19 = 457.10 : x
  2. Step 2: Convert to fraction form
    1,278.78/1,918.19 = 457.10/x
  3. Step 3: Cross multiply
    1,278.78x = 1,918.19 × 457.10
  4. Step 4: Simplify right side
    1,278.78x = 876,804.65
  5. Step 5: Solve for x
    x = 876,804.65/1,278.78
  6. Step 6: Final answer
    x = 685.66

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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.