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Finding the Fourth Proportional to 939.02, 1,297.50 and 678.20

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Solution

The fourth proportional to 939.02, 1,297.50 and 678.20 is: 937.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    939.02 : 1,297.50 = 678.20 : x
  2. Step 2: Convert to fraction form
    939.02/1,297.50 = 678.20/x
  3. Step 3: Cross multiply
    939.02x = 1,297.50 × 678.20
  4. Step 4: Simplify right side
    939.02x = 879,964.50
  5. Step 5: Solve for x
    x = 879,964.50/939.02
  6. Step 6: Final answer
    x = 937.11

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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.