Finding the Fourth Proportional to 128.19, 177.08 and 122.12
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Solution
The fourth proportional to 128.19, 177.08 and 122.12 is: 168.68
Step by Step Solution
- Step 1: Write the proportion equation
128.19 : 177.08 = 122.12 : x - Step 2: Convert to fraction form
128.19/177.08 = 122.12/x - Step 3: Cross multiply
128.19x = 177.08 × 122.12 - Step 4: Simplify right side
128.19x = 21,623.51 - Step 5: Solve for x
x = 21,623.51/128.19 - Step 6: Final answer
x = 168.68
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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.