Finding the Fourth Proportional to 84.36, 115.58 and 81.12
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Solution
The fourth proportional to 84.36, 115.58 and 81.12 is: 111.14
Step by Step Solution
- Step 1: Write the proportion equation
84.36 : 115.58 = 81.12 : x - Step 2: Convert to fraction form
84.36/115.58 = 81.12/x - Step 3: Cross multiply
84.36x = 115.58 × 81.12 - Step 4: Simplify right side
84.36x = 9,375.44 - Step 5: Solve for x
x = 9,375.44/84.36 - Step 6: Final answer
x = 111.14
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Why These Related Problems?
These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.