Finding the Fourth Proportional to 120.80, 180.68 and 91.59
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Solution
The fourth proportional to 120.80, 180.68 and 91.59 is: 136.99
Step by Step Solution
- Step 1: Write the proportion equation
120.80 : 180.68 = 91.59 : x - Step 2: Convert to fraction form
120.80/180.68 = 91.59/x - Step 3: Cross multiply
120.80x = 180.68 × 91.59 - Step 4: Simplify right side
120.80x = 16,548.02 - Step 5: Solve for x
x = 16,548.02/120.80 - Step 6: Final answer
x = 136.99
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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.