Home / 1,290.36-1,935.78-412.80

Finding the Fourth Proportional to 1,290.36, 1,935.78 and 412.80

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Solution

The fourth proportional to 1,290.36, 1,935.78 and 412.80 is: 619.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.36 : 1,935.78 = 412.80 : x
  2. Step 2: Convert to fraction form
    1,290.36/1,935.78 = 412.80/x
  3. Step 3: Cross multiply
    1,290.36x = 1,935.78 × 412.80
  4. Step 4: Simplify right side
    1,290.36x = 799,089.98
  5. Step 5: Solve for x
    x = 799,089.98/1,290.36
  6. Step 6: Final answer
    x = 619.28

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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.