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Finding the Fourth Proportional to 1,209.08, 1,668.36 and 685.16

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Solution

The fourth proportional to 1,209.08, 1,668.36 and 685.16 is: 945.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.08 : 1,668.36 = 685.16 : x
  2. Step 2: Convert to fraction form
    1,209.08/1,668.36 = 685.16/x
  3. Step 3: Cross multiply
    1,209.08x = 1,668.36 × 685.16
  4. Step 4: Simplify right side
    1,209.08x = 1,143,093.54
  5. Step 5: Solve for x
    x = 1,143,093.54/1,209.08
  6. Step 6: Final answer
    x = 945.42

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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.