Home / 1,212.21-1,818.48-390.39

Finding the Fourth Proportional to 1,212.21, 1,818.48 and 390.39

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Solution

The fourth proportional to 1,212.21, 1,818.48 and 390.39 is: 585.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.21 : 1,818.48 = 390.39 : x
  2. Step 2: Convert to fraction form
    1,212.21/1,818.48 = 390.39/x
  3. Step 3: Cross multiply
    1,212.21x = 1,818.48 × 390.39
  4. Step 4: Simplify right side
    1,212.21x = 709,916.41
  5. Step 5: Solve for x
    x = 709,916.41/1,212.21
  6. Step 6: Final answer
    x = 585.64

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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.