Home / 1,212.09-1,818.49-390.35

Finding the Fourth Proportional to 1,212.09, 1,818.49 and 390.35

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Solution

The fourth proportional to 1,212.09, 1,818.49 and 390.35 is: 585.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.09 : 1,818.49 = 390.35 : x
  2. Step 2: Convert to fraction form
    1,212.09/1,818.49 = 390.35/x
  3. Step 3: Cross multiply
    1,212.09x = 1,818.49 × 390.35
  4. Step 4: Simplify right side
    1,212.09x = 709,838.48
  5. Step 5: Solve for x
    x = 709,838.48/1,212.09
  6. Step 6: Final answer
    x = 585.63

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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.