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Finding the Fourth Proportional to 1,378.10, 2,064.41 and 645.45

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Solution

The fourth proportional to 1,378.10, 2,064.41 and 645.45 is: 966.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.10 : 2,064.41 = 645.45 : x
  2. Step 2: Convert to fraction form
    1,378.10/2,064.41 = 645.45/x
  3. Step 3: Cross multiply
    1,378.10x = 2,064.41 × 645.45
  4. Step 4: Simplify right side
    1,378.10x = 1,332,470.21
  5. Step 5: Solve for x
    x = 1,332,470.21/1,378.10
  6. Step 6: Final answer
    x = 966.89

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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.