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Finding the Fourth Proportional to 421.49, 629.34 and 343.58

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Solution

The fourth proportional to 421.49, 629.34 and 343.58 is: 513.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.49 : 629.34 = 343.58 : x
  2. Step 2: Convert to fraction form
    421.49/629.34 = 343.58/x
  3. Step 3: Cross multiply
    421.49x = 629.34 × 343.58
  4. Step 4: Simplify right side
    421.49x = 216,225.49
  5. Step 5: Solve for x
    x = 216,225.49/421.49
  6. Step 6: Final answer
    x = 513.01

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.