Home / 1,290.13-1,935.28-640.69

Finding the Fourth Proportional to 1,290.13, 1,935.28 and 640.69

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Solution

The fourth proportional to 1,290.13, 1,935.28 and 640.69 is: 961.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.13 : 1,935.28 = 640.69 : x
  2. Step 2: Convert to fraction form
    1,290.13/1,935.28 = 640.69/x
  3. Step 3: Cross multiply
    1,290.13x = 1,935.28 × 640.69
  4. Step 4: Simplify right side
    1,290.13x = 1,239,914.54
  5. Step 5: Solve for x
    x = 1,239,914.54/1,290.13
  6. Step 6: Final answer
    x = 961.08

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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.