Finding the Fourth Proportional to 138.15, 207.36 and 107.64
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Solution
The fourth proportional to 138.15, 207.36 and 107.64 is: 161.57
Step by Step Solution
- Step 1: Write the proportion equation
138.15 : 207.36 = 107.64 : x - Step 2: Convert to fraction form
138.15/207.36 = 107.64/x - Step 3: Cross multiply
138.15x = 207.36 × 107.64 - Step 4: Simplify right side
138.15x = 22,320.23 - Step 5: Solve for x
x = 22,320.23/138.15 - Step 6: Final answer
x = 161.57
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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.