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Finding the Fourth Proportional to 2,880, 3,975.12 and 1,638.72

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Solution

The fourth proportional to 2,880, 3,975.12 and 1,638.72 is: 2,261.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,880 : 3,975.12 = 1,638.72 : x
  2. Step 2: Convert to fraction form
    2,880/3,975.12 = 1,638.72/x
  3. Step 3: Cross multiply
    2,880x = 3,975.12 × 1,638.72
  4. Step 4: Simplify right side
    2,880x = 6,514,108.65
  5. Step 5: Solve for x
    x = 6,514,108.65/2,880
  6. Step 6: Final answer
    x = 2,261.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.