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Finding the Fourth Proportional to 777.28, 1,072.68 and 445.80

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Solution

The fourth proportional to 777.28, 1,072.68 and 445.80 is: 615.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    777.28 : 1,072.68 = 445.80 : x
  2. Step 2: Convert to fraction form
    777.28/1,072.68 = 445.80/x
  3. Step 3: Cross multiply
    777.28x = 1,072.68 × 445.80
  4. Step 4: Simplify right side
    777.28x = 478,200.74
  5. Step 5: Solve for x
    x = 478,200.74/777.28
  6. Step 6: Final answer
    x = 615.22

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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.