Finding the Third Proportional to 81.75 and 90
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Solution
The third proportional to 81.75 and 90 is: 99.08
Step by Step Solution
- Step 1: Write the proportion equation
81.75 : 90 = 90 : x - Step 2: Convert to fraction form
81.75/90 = 90/x - Step 3: Cross multiply
81.75x = 90 × 90 - Step 4: Simplify right side
81.75x = 8,100 - Step 5: Solve for x
x = 8,100/81.75 - Step 6: Final answer
x = 99.08
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These problems maintain the same ratio (1.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.