Home / 1,290.31-1,935.60-412.60

Finding the Fourth Proportional to 1,290.31, 1,935.60 and 412.60

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Solution

The fourth proportional to 1,290.31, 1,935.60 and 412.60 is: 618.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.31 : 1,935.60 = 412.60 : x
  2. Step 2: Convert to fraction form
    1,290.31/1,935.60 = 412.60/x
  3. Step 3: Cross multiply
    1,290.31x = 1,935.60 × 412.60
  4. Step 4: Simplify right side
    1,290.31x = 798,628.56
  5. Step 5: Solve for x
    x = 798,628.56/1,290.31
  6. Step 6: Final answer
    x = 618.94

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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.