Finding the Fourth Proportional to 86.96, 129.49 and 85.99
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Solution
The fourth proportional to 86.96, 129.49 and 85.99 is: 128.05
Step by Step Solution
- Step 1: Write the proportion equation
86.96 : 129.49 = 85.99 : x - Step 2: Convert to fraction form
86.96/129.49 = 85.99/x - Step 3: Cross multiply
86.96x = 129.49 × 85.99 - Step 4: Simplify right side
86.96x = 11,135.03 - Step 5: Solve for x
x = 11,135.03/86.96 - Step 6: Final answer
x = 128.05
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.