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Finding the Fourth Proportional to 719.80, 1,080.50 and 287.26

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Solution

The fourth proportional to 719.80, 1,080.50 and 287.26 is: 431.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.80 : 1,080.50 = 287.26 : x
  2. Step 2: Convert to fraction form
    719.80/1,080.50 = 287.26/x
  3. Step 3: Cross multiply
    719.80x = 1,080.50 × 287.26
  4. Step 4: Simplify right side
    719.80x = 310,384.43
  5. Step 5: Solve for x
    x = 310,384.43/719.80
  6. Step 6: Final answer
    x = 431.21

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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.