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Finding the Fourth Proportional to 421.80, 629.51 and 410.87

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Solution

The fourth proportional to 421.80, 629.51 and 410.87 is: 613.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.80 : 629.51 = 410.87 : x
  2. Step 2: Convert to fraction form
    421.80/629.51 = 410.87/x
  3. Step 3: Cross multiply
    421.80x = 629.51 × 410.87
  4. Step 4: Simplify right side
    421.80x = 258,643.63
  5. Step 5: Solve for x
    x = 258,643.63/421.80
  6. Step 6: Final answer
    x = 613.19

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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.