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Finding the Fourth Proportional to 891.85, 1,338 and 720.08

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Solution

The fourth proportional to 891.85, 1,338 and 720.08 is: 1,080.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.85 : 1,338 = 720.08 : x
  2. Step 2: Convert to fraction form
    891.85/1,338 = 720.08/x
  3. Step 3: Cross multiply
    891.85x = 1,338 × 720.08
  4. Step 4: Simplify right side
    891.85x = 963,467.04
  5. Step 5: Solve for x
    x = 963,467.04/891.85
  6. Step 6: Final answer
    x = 1,080.30

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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.