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Finding the Fourth Proportional to 622.50, 858.72 and 389.22

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Solution

The fourth proportional to 622.50, 858.72 and 389.22 is: 536.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    622.50 : 858.72 = 389.22 : x
  2. Step 2: Convert to fraction form
    622.50/858.72 = 389.22/x
  3. Step 3: Cross multiply
    622.50x = 858.72 × 389.22
  4. Step 4: Simplify right side
    622.50x = 334,231.00
  5. Step 5: Solve for x
    x = 334,231.00/622.50
  6. Step 6: Final answer
    x = 536.92

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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.