Finding the Fourth Proportional to 221.18, 331.78 and 84.21
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Solution
The fourth proportional to 221.18, 331.78 and 84.21 is: 126.33
Step by Step Solution
- Step 1: Write the proportion equation
221.18 : 331.78 = 84.21 : x - Step 2: Convert to fraction form
221.18/331.78 = 84.21/x - Step 3: Cross multiply
221.18x = 331.78 × 84.21 - Step 4: Simplify right side
221.18x = 27,941.05 - Step 5: Solve for x
x = 27,941.05/221.18 - Step 6: Final answer
x = 126.33
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.