Finding the Fourth Proportional to 121.80, 168.12 and 84.99
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Solution
The fourth proportional to 121.80, 168.12 and 84.99 is: 117.31
Step by Step Solution
- Step 1: Write the proportion equation
121.80 : 168.12 = 84.99 : x - Step 2: Convert to fraction form
121.80/168.12 = 84.99/x - Step 3: Cross multiply
121.80x = 168.12 × 84.99 - Step 4: Simplify right side
121.80x = 14,288.52 - Step 5: Solve for x
x = 14,288.52/121.80 - Step 6: Final answer
x = 117.31
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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.