Finding the Fourth Proportional to 128.15, 192.18 and 55.00
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Solution
The fourth proportional to 128.15, 192.18 and 55.00 is: 82.49
Step by Step Solution
- Step 1: Write the proportion equation
128.15 : 192.18 = 55.00 : x - Step 2: Convert to fraction form
128.15/192.18 = 55.00/x - Step 3: Cross multiply
128.15x = 192.18 × 55.00 - Step 4: Simplify right side
128.15x = 10,570.21 - Step 5: Solve for x
x = 10,570.21/128.15 - Step 6: Final answer
x = 82.49
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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.