Finding the Fourth Proportional to 86.68, 129.99 and 25.80
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Solution
The fourth proportional to 86.68, 129.99 and 25.80 is: 38.68
Step by Step Solution
- Step 1: Write the proportion equation
86.68 : 129.99 = 25.80 : x - Step 2: Convert to fraction form
86.68/129.99 = 25.80/x - Step 3: Cross multiply
86.68x = 129.99 × 25.80 - Step 4: Simplify right side
86.68x = 3,352.96 - Step 5: Solve for x
x = 3,352.96/86.68 - Step 6: Final answer
x = 38.68
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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.