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Finding the Fourth Proportional to 647.80, 894.36 and 399.46

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Solution

The fourth proportional to 647.80, 894.36 and 399.46 is: 551.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.80 : 894.36 = 399.46 : x
  2. Step 2: Convert to fraction form
    647.80/894.36 = 399.46/x
  3. Step 3: Cross multiply
    647.80x = 894.36 × 399.46
  4. Step 4: Simplify right side
    647.80x = 357,261.05
  5. Step 5: Solve for x
    x = 357,261.05/647.80
  6. Step 6: Final answer
    x = 551.50

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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.