Finding the Fourth Proportional to 129.81, 194.99 and 81.75
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Solution
The fourth proportional to 129.81, 194.99 and 81.75 is: 122.80
Step by Step Solution
- Step 1: Write the proportion equation
129.81 : 194.99 = 81.75 : x - Step 2: Convert to fraction form
129.81/194.99 = 81.75/x - Step 3: Cross multiply
129.81x = 194.99 × 81.75 - Step 4: Simplify right side
129.81x = 15,940.43 - Step 5: Solve for x
x = 15,940.43/129.81 - Step 6: Final answer
x = 122.80
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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.