Finding the Fourth Proportional to 110, 165 and 86
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Solution
The fourth proportional to 110, 165 and 86 is: 129
Step by Step Solution
- Step 1: Write the proportion equation
110 : 165 = 86 : x - Step 2: Convert to fraction form
110/165 = 86/x - Step 3: Cross multiply
110x = 165 × 86 - Step 4: Simplify right side
110x = 14,190 - Step 5: Solve for x
x = 14,190/110 - Step 6: Final answer
x = 129
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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.