Finding the Fourth Proportional to 138.21, 207.09 and 76.44
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Solution
The fourth proportional to 138.21, 207.09 and 76.44 is: 114.54
Step by Step Solution
- Step 1: Write the proportion equation
138.21 : 207.09 = 76.44 : x - Step 2: Convert to fraction form
138.21/207.09 = 76.44/x - Step 3: Cross multiply
138.21x = 207.09 × 76.44 - Step 4: Simplify right side
138.21x = 15,829.96 - Step 5: Solve for x
x = 15,829.96/138.21 - Step 6: Final answer
x = 114.54
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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.