Finding the Fourth Proportional to 81.24, 120.99 and 79.11
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Solution
The fourth proportional to 81.24, 120.99 and 79.11 is: 117.82
Step by Step Solution
- Step 1: Write the proportion equation
81.24 : 120.99 = 79.11 : x - Step 2: Convert to fraction form
81.24/120.99 = 79.11/x - Step 3: Cross multiply
81.24x = 120.99 × 79.11 - Step 4: Simplify right side
81.24x = 9,571.52 - Step 5: Solve for x
x = 9,571.52/81.24 - Step 6: Final answer
x = 117.82
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.