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Finding the Fourth Proportional to 505.81, 697.80 and 328.78

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Solution

The fourth proportional to 505.81, 697.80 and 328.78 is: 453.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.81 : 697.80 = 328.78 : x
  2. Step 2: Convert to fraction form
    505.81/697.80 = 328.78/x
  3. Step 3: Cross multiply
    505.81x = 697.80 × 328.78
  4. Step 4: Simplify right side
    505.81x = 229,422.68
  5. Step 5: Solve for x
    x = 229,422.68/505.81
  6. Step 6: Final answer
    x = 453.57

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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.