Finding the Fourth Proportional to 100.76, 139.06 and 57.09
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Solution
The fourth proportional to 100.76, 139.06 and 57.09 is: 78.80
Step by Step Solution
- Step 1: Write the proportion equation
100.76 : 139.06 = 57.09 : x - Step 2: Convert to fraction form
100.76/139.06 = 57.09/x - Step 3: Cross multiply
100.76x = 139.06 × 57.09 - Step 4: Simplify right side
100.76x = 7,939.53 - Step 5: Solve for x
x = 7,939.53/100.76 - Step 6: Final answer
x = 78.80
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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.