Home / 1,278.70-1,918.39-457.05

Finding the Fourth Proportional to 1,278.70, 1,918.39 and 457.05

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Solution

The fourth proportional to 1,278.70, 1,918.39 and 457.05 is: 685.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.70 : 1,918.39 = 457.05 : x
  2. Step 2: Convert to fraction form
    1,278.70/1,918.39 = 457.05/x
  3. Step 3: Cross multiply
    1,278.70x = 1,918.39 × 457.05
  4. Step 4: Simplify right side
    1,278.70x = 876,800.15
  5. Step 5: Solve for x
    x = 876,800.15/1,278.70
  6. Step 6: Final answer
    x = 685.70

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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.