Home / 3,120-4,680-1,272.12

Finding the Fourth Proportional to 3,120, 4,680 and 1,272.12

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Solution

The fourth proportional to 3,120, 4,680 and 1,272.12 is: 1,908.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,120 : 4,680 = 1,272.12 : x
  2. Step 2: Convert to fraction form
    3,120/4,680 = 1,272.12/x
  3. Step 3: Cross multiply
    3,120x = 4,680 × 1,272.12
  4. Step 4: Simplify right side
    3,120x = 5,953,521.60
  5. Step 5: Solve for x
    x = 5,953,521.60/3,120
  6. Step 6: Final answer
    x = 1,908.18

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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.