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Finding the Fourth Proportional to 838.09, 1,253.36 and 640.49

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Solution

The fourth proportional to 838.09, 1,253.36 and 640.49 is: 957.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.09 : 1,253.36 = 640.49 : x
  2. Step 2: Convert to fraction form
    838.09/1,253.36 = 640.49/x
  3. Step 3: Cross multiply
    838.09x = 1,253.36 × 640.49
  4. Step 4: Simplify right side
    838.09x = 802,756.64
  5. Step 5: Solve for x
    x = 802,756.64/838.09
  6. Step 6: Final answer
    x = 957.84

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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.