Finding the Fourth Proportional to 139.34, 192.79 and 121.90
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Solution
The fourth proportional to 139.34, 192.79 and 121.90 is: 168.66
Step by Step Solution
- Step 1: Write the proportion equation
139.34 : 192.79 = 121.90 : x - Step 2: Convert to fraction form
139.34/192.79 = 121.90/x - Step 3: Cross multiply
139.34x = 192.79 × 121.90 - Step 4: Simplify right side
139.34x = 23,501.10 - Step 5: Solve for x
x = 23,501.10/139.34 - Step 6: Final answer
x = 168.66
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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.