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Finding the Fourth Proportional to 315.80, 435.84 and 305.72

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Solution

The fourth proportional to 315.80, 435.84 and 305.72 is: 421.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.80 : 435.84 = 305.72 : x
  2. Step 2: Convert to fraction form
    315.80/435.84 = 305.72/x
  3. Step 3: Cross multiply
    315.80x = 435.84 × 305.72
  4. Step 4: Simplify right side
    315.80x = 133,245.00
  5. Step 5: Solve for x
    x = 133,245.00/315.80
  6. Step 6: Final answer
    x = 421.93

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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.