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Finding the Fourth Proportional to 940.07, 1,297.05 and 640.78

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Solution

The fourth proportional to 940.07, 1,297.05 and 640.78 is: 884.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    940.07 : 1,297.05 = 640.78 : x
  2. Step 2: Convert to fraction form
    940.07/1,297.05 = 640.78/x
  3. Step 3: Cross multiply
    940.07x = 1,297.05 × 640.78
  4. Step 4: Simplify right side
    940.07x = 831,118.05
  5. Step 5: Solve for x
    x = 831,118.05/940.07
  6. Step 6: Final answer
    x = 884.10

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1.5x scale

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.