Finding the Fourth Proportional to 123.84, 170.84 and 72.09
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Solution
The fourth proportional to 123.84, 170.84 and 72.09 is: 99.45
Step by Step Solution
- Step 1: Write the proportion equation
123.84 : 170.84 = 72.09 : x - Step 2: Convert to fraction form
123.84/170.84 = 72.09/x - Step 3: Cross multiply
123.84x = 170.84 × 72.09 - Step 4: Simplify right side
123.84x = 12,315.86 - Step 5: Solve for x
x = 12,315.86/123.84 - Step 6: Final answer
x = 99.45
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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.