Finding the Fourth Proportional to 86.21, 129.42 and 51.99
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Solution
The fourth proportional to 86.21, 129.42 and 51.99 is: 78.04
Step by Step Solution
- Step 1: Write the proportion equation
86.21 : 129.42 = 51.99 : x - Step 2: Convert to fraction form
86.21/129.42 = 51.99/x - Step 3: Cross multiply
86.21x = 129.42 × 51.99 - Step 4: Simplify right side
86.21x = 6,728.06 - Step 5: Solve for x
x = 6,728.06/86.21 - Step 6: Final answer
x = 78.04
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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.