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Finding the Fourth Proportional to 637.70, 879.77 and 389.00

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Solution

The fourth proportional to 637.70, 879.77 and 389.00 is: 536.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.70 : 879.77 = 389.00 : x
  2. Step 2: Convert to fraction form
    637.70/879.77 = 389.00/x
  3. Step 3: Cross multiply
    637.70x = 879.77 × 389.00
  4. Step 4: Simplify right side
    637.70x = 342,224.19
  5. Step 5: Solve for x
    x = 342,224.19/637.70
  6. Step 6: Final answer
    x = 536.66

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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.