Finding the Fourth Proportional to 129.19, 178.43 and 87.67
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Solution
The fourth proportional to 129.19, 178.43 and 87.67 is: 121.09
Step by Step Solution
- Step 1: Write the proportion equation
129.19 : 178.43 = 87.67 : x - Step 2: Convert to fraction form
129.19/178.43 = 87.67/x - Step 3: Cross multiply
129.19x = 178.43 × 87.67 - Step 4: Simplify right side
129.19x = 15,642.91 - Step 5: Solve for x
x = 15,642.91/129.19 - Step 6: Final answer
x = 121.09
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.