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Finding the Fourth Proportional to 815.24, 1,215.12 and 808.86

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Solution

The fourth proportional to 815.24, 1,215.12 and 808.86 is: 1,205.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.24 : 1,215.12 = 808.86 : x
  2. Step 2: Convert to fraction form
    815.24/1,215.12 = 808.86/x
  3. Step 3: Cross multiply
    815.24x = 1,215.12 × 808.86
  4. Step 4: Simplify right side
    815.24x = 982,857.41
  5. Step 5: Solve for x
    x = 982,857.41/815.24
  6. Step 6: Final answer
    x = 1,205.61

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.