Home / 1,208.34-1,811.88-428.22

Finding the Fourth Proportional to 1,208.34, 1,811.88 and 428.22

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Solution

The fourth proportional to 1,208.34, 1,811.88 and 428.22 is: 642.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,208.34 : 1,811.88 = 428.22 : x
  2. Step 2: Convert to fraction form
    1,208.34/1,811.88 = 428.22/x
  3. Step 3: Cross multiply
    1,208.34x = 1,811.88 × 428.22
  4. Step 4: Simplify right side
    1,208.34x = 775,883.25
  5. Step 5: Solve for x
    x = 775,883.25/1,208.34
  6. Step 6: Final answer
    x = 642.11

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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.