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Finding the Fourth Proportional to 708.20, 977.57 and 685.11

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Solution

The fourth proportional to 708.20, 977.57 and 685.11 is: 945.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    708.20 : 977.57 = 685.11 : x
  2. Step 2: Convert to fraction form
    708.20/977.57 = 685.11/x
  3. Step 3: Cross multiply
    708.20x = 977.57 × 685.11
  4. Step 4: Simplify right side
    708.20x = 669,742.98
  5. Step 5: Solve for x
    x = 669,742.98/708.20
  6. Step 6: Final answer
    x = 945.70

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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.