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Finding the Fourth Proportional to 620.50, 931.18 and 438.06

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Solution

The fourth proportional to 620.50, 931.18 and 438.06 is: 657.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.50 : 931.18 = 438.06 : x
  2. Step 2: Convert to fraction form
    620.50/931.18 = 438.06/x
  3. Step 3: Cross multiply
    620.50x = 931.18 × 438.06
  4. Step 4: Simplify right side
    620.50x = 407,912.71
  5. Step 5: Solve for x
    x = 407,912.71/620.50
  6. Step 6: Final answer
    x = 657.39

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.