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Finding the Fourth Proportional to 688.80, 996.60 and 688.80

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Solution

The fourth proportional to 688.80, 996.60 and 688.80 is: 996.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.80 : 996.60 = 688.80 : x
  2. Step 2: Convert to fraction form
    688.80/996.60 = 688.80/x
  3. Step 3: Cross multiply
    688.80x = 996.60 × 688.80
  4. Step 4: Simplify right side
    688.80x = 686,458.08
  5. Step 5: Solve for x
    x = 686,458.08/688.80
  6. Step 6: Final answer
    x = 996.60

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.