Finding the Fourth Proportional to 21.14, 31.68 and 14
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Solution
The fourth proportional to 21.14, 31.68 and 14 is: 20.98
Step by Step Solution
- Step 1: Write the proportion equation
21.14 : 31.68 = 14 : x - Step 2: Convert to fraction form
21.14/31.68 = 14/x - Step 3: Cross multiply
21.14x = 31.68 × 14 - Step 4: Simplify right side
21.14x = 443.52 - Step 5: Solve for x
x = 443.52/21.14 - Step 6: Final answer
x = 20.98
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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.