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Finding the Fourth Proportional to 1,289.58, 1,934.55 and 640.34

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Solution

The fourth proportional to 1,289.58, 1,934.55 and 640.34 is: 960.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.58 : 1,934.55 = 640.34 : x
  2. Step 2: Convert to fraction form
    1,289.58/1,934.55 = 640.34/x
  3. Step 3: Cross multiply
    1,289.58x = 1,934.55 × 640.34
  4. Step 4: Simplify right side
    1,289.58x = 1,238,769.75
  5. Step 5: Solve for x
    x = 1,238,769.75/1,289.58
  6. Step 6: Final answer
    x = 960.60

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.