Finding the Fourth Proportional to 209.19, 313.99 and 128.19
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Solution
The fourth proportional to 209.19, 313.99 and 128.19 is: 192.41
Step by Step Solution
- Step 1: Write the proportion equation
209.19 : 313.99 = 128.19 : x - Step 2: Convert to fraction form
209.19/313.99 = 128.19/x - Step 3: Cross multiply
209.19x = 313.99 × 128.19 - Step 4: Simplify right side
209.19x = 40,250.06 - Step 5: Solve for x
x = 40,250.06/209.19 - Step 6: Final answer
x = 192.41
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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.