Finding the Fourth Proportional to 42.38, 63.54 and 20.99
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Solution
The fourth proportional to 42.38, 63.54 and 20.99 is: 31.47
Step by Step Solution
- Step 1: Write the proportion equation
42.38 : 63.54 = 20.99 : x - Step 2: Convert to fraction form
42.38/63.54 = 20.99/x - Step 3: Cross multiply
42.38x = 63.54 × 20.99 - Step 4: Simplify right side
42.38x = 1,333.70 - Step 5: Solve for x
x = 1,333.70/42.38 - Step 6: Final answer
x = 31.47
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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.