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Finding the Fourth Proportional to 645.51, 890.79 and 350.78

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Solution

The fourth proportional to 645.51, 890.79 and 350.78 is: 484.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.51 : 890.79 = 350.78 : x
  2. Step 2: Convert to fraction form
    645.51/890.79 = 350.78/x
  3. Step 3: Cross multiply
    645.51x = 890.79 × 350.78
  4. Step 4: Simplify right side
    645.51x = 312,465.55
  5. Step 5: Solve for x
    x = 312,465.55/645.51
  6. Step 6: Final answer
    x = 484.06

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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.