Finding the Third Proportional to 81.75 and 84
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Solution
The third proportional to 81.75 and 84 is: 86.31
Step by Step Solution
- Step 1: Write the proportion equation
81.75 : 84 = 84 : x - Step 2: Convert to fraction form
81.75/84 = 84/x - Step 3: Cross multiply
81.75x = 84 × 84 - Step 4: Simplify right side
81.75x = 7,056 - Step 5: Solve for x
x = 7,056/81.75 - Step 6: Final answer
x = 86.31
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Why These Related Problems?
These problems maintain the same ratio (1.03) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.