Finding the Fourth Proportional to 81.12, 121.68 and 63.99
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Solution
The fourth proportional to 81.12, 121.68 and 63.99 is: 95.99
Step by Step Solution
- Step 1: Write the proportion equation
81.12 : 121.68 = 63.99 : x - Step 2: Convert to fraction form
81.12/121.68 = 63.99/x - Step 3: Cross multiply
81.12x = 121.68 × 63.99 - Step 4: Simplify right side
81.12x = 7,786.30 - Step 5: Solve for x
x = 7,786.30/81.12 - Step 6: Final answer
x = 95.99
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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.