Finding the Fourth Proportional to 100.18, 138.12 and 81.82
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Solution
The fourth proportional to 100.18, 138.12 and 81.82 is: 112.81
Step by Step Solution
- Step 1: Write the proportion equation
100.18 : 138.12 = 81.82 : x - Step 2: Convert to fraction form
100.18/138.12 = 81.82/x - Step 3: Cross multiply
100.18x = 138.12 × 81.82 - Step 4: Simplify right side
100.18x = 11,300.98 - Step 5: Solve for x
x = 11,300.98/100.18 - Step 6: Final answer
x = 112.81
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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.