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Finding the Fourth Proportional to 643.68, 889.32 and 513.84

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Solution

The fourth proportional to 643.68, 889.32 and 513.84 is: 709.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.68 : 889.32 = 513.84 : x
  2. Step 2: Convert to fraction form
    643.68/889.32 = 513.84/x
  3. Step 3: Cross multiply
    643.68x = 889.32 × 513.84
  4. Step 4: Simplify right side
    643.68x = 456,968.19
  5. Step 5: Solve for x
    x = 456,968.19/643.68
  6. Step 6: Final answer
    x = 709.93

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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.