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Finding the Fourth Proportional to 1,942.05, 2,912.41 and 643.21

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Solution

The fourth proportional to 1,942.05, 2,912.41 and 643.21 is: 964.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,942.05 : 2,912.41 = 643.21 : x
  2. Step 2: Convert to fraction form
    1,942.05/2,912.41 = 643.21/x
  3. Step 3: Cross multiply
    1,942.05x = 2,912.41 × 643.21
  4. Step 4: Simplify right side
    1,942.05x = 1,873,291.24
  5. Step 5: Solve for x
    x = 1,873,291.24/1,942.05
  6. Step 6: Final answer
    x = 964.59

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1.5x scale

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.