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Finding the Fourth Proportional to 420.99, 628.29 and 410.05

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Solution

The fourth proportional to 420.99, 628.29 and 410.05 is: 611.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.99 : 628.29 = 410.05 : x
  2. Step 2: Convert to fraction form
    420.99/628.29 = 410.05/x
  3. Step 3: Cross multiply
    420.99x = 628.29 × 410.05
  4. Step 4: Simplify right side
    420.99x = 257,629.29
  5. Step 5: Solve for x
    x = 257,629.29/420.99
  6. Step 6: Final answer
    x = 611.97

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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.