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Finding the Fourth Proportional to 690.75, 1,036.13 and 203.79

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Solution

The fourth proportional to 690.75, 1,036.13 and 203.79 is: 305.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.75 : 1,036.13 = 203.79 : x
  2. Step 2: Convert to fraction form
    690.75/1,036.13 = 203.79/x
  3. Step 3: Cross multiply
    690.75x = 1,036.13 × 203.79
  4. Step 4: Simplify right side
    690.75x = 211,152.93
  5. Step 5: Solve for x
    x = 211,152.93/690.75
  6. Step 6: Final answer
    x = 305.69

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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.