Finding the Fourth Proportional to 84.12, 115.77 and 71.79
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Solution
The fourth proportional to 84.12, 115.77 and 71.79 is: 98.80
Step by Step Solution
- Step 1: Write the proportion equation
84.12 : 115.77 = 71.79 : x - Step 2: Convert to fraction form
84.12/115.77 = 71.79/x - Step 3: Cross multiply
84.12x = 115.77 × 71.79 - Step 4: Simplify right side
84.12x = 8,311.13 - Step 5: Solve for x
x = 8,311.13/84.12 - Step 6: Final answer
x = 98.80
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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.