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Finding the Fourth Proportional to 698.80, 980.75 and 698.80

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Solution

The fourth proportional to 698.80, 980.75 and 698.80 is: 980.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    698.80 : 980.75 = 698.80 : x
  2. Step 2: Convert to fraction form
    698.80/980.75 = 698.80/x
  3. Step 3: Cross multiply
    698.80x = 980.75 × 698.80
  4. Step 4: Simplify right side
    698.80x = 685,348.10
  5. Step 5: Solve for x
    x = 685,348.10/698.80
  6. Step 6: Final answer
    x = 980.75

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.