Finding the Fourth Proportional to 128.76, 192.71 and 98.15
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Solution
The fourth proportional to 128.76, 192.71 and 98.15 is: 146.90
Step by Step Solution
- Step 1: Write the proportion equation
128.76 : 192.71 = 98.15 : x - Step 2: Convert to fraction form
128.76/192.71 = 98.15/x - Step 3: Cross multiply
128.76x = 192.71 × 98.15 - Step 4: Simplify right side
128.76x = 18,914.49 - Step 5: Solve for x
x = 18,914.49/128.76 - Step 6: Final answer
x = 146.90
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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.