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Finding the Fourth Proportional to 784.20, 1,080.94 and 618.15

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Solution

The fourth proportional to 784.20, 1,080.94 and 618.15 is: 852.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.20 : 1,080.94 = 618.15 : x
  2. Step 2: Convert to fraction form
    784.20/1,080.94 = 618.15/x
  3. Step 3: Cross multiply
    784.20x = 1,080.94 × 618.15
  4. Step 4: Simplify right side
    784.20x = 668,183.06
  5. Step 5: Solve for x
    x = 668,183.06/784.20
  6. Step 6: Final answer
    x = 852.06

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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.