Finding the Fourth Proportional to 98.21, 135.42 and 81.80
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Solution
The fourth proportional to 98.21, 135.42 and 81.80 is: 112.79
Step by Step Solution
- Step 1: Write the proportion equation
98.21 : 135.42 = 81.80 : x - Step 2: Convert to fraction form
98.21/135.42 = 81.80/x - Step 3: Cross multiply
98.21x = 135.42 × 81.80 - Step 4: Simplify right side
98.21x = 11,076.68 - Step 5: Solve for x
x = 11,076.68/98.21 - Step 6: Final answer
x = 112.79
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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.