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Finding the Fourth Proportional to 891.12, 1,336.80 and 378

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Solution

The fourth proportional to 891.12, 1,336.80 and 378 is: 567.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.12 : 1,336.80 = 378 : x
  2. Step 2: Convert to fraction form
    891.12/1,336.80 = 378/x
  3. Step 3: Cross multiply
    891.12x = 1,336.80 × 378
  4. Step 4: Simplify right side
    891.12x = 505,310.40
  5. Step 5: Solve for x
    x = 505,310.40/891.12
  6. Step 6: Final answer
    x = 567.05

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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.