Finding the Fourth Proportional to 138.21, 207.15 and 107.68
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Solution
The fourth proportional to 138.21, 207.15 and 107.68 is: 161.39
Step by Step Solution
- Step 1: Write the proportion equation
138.21 : 207.15 = 107.68 : x - Step 2: Convert to fraction form
138.21/207.15 = 107.68/x - Step 3: Cross multiply
138.21x = 207.15 × 107.68 - Step 4: Simplify right side
138.21x = 22,305.91 - Step 5: Solve for x
x = 22,305.91/138.21 - Step 6: Final answer
x = 161.39
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.