Finding the Fourth Proportional to 87.21, 120.08 and 79.11
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Solution
The fourth proportional to 87.21, 120.08 and 79.11 is: 108.92
Step by Step Solution
- Step 1: Write the proportion equation
87.21 : 120.08 = 79.11 : x - Step 2: Convert to fraction form
87.21/120.08 = 79.11/x - Step 3: Cross multiply
87.21x = 120.08 × 79.11 - Step 4: Simplify right side
87.21x = 9,499.13 - Step 5: Solve for x
x = 9,499.13/87.21 - Step 6: Final answer
x = 108.92
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.