Finding the Fourth Proportional to 100.87, 139.02 and 79.09
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Solution
The fourth proportional to 100.87, 139.02 and 79.09 is: 109.00
Step by Step Solution
- Step 1: Write the proportion equation
100.87 : 139.02 = 79.09 : x - Step 2: Convert to fraction form
100.87/139.02 = 79.09/x - Step 3: Cross multiply
100.87x = 139.02 × 79.09 - Step 4: Simplify right side
100.87x = 10,995.09 - Step 5: Solve for x
x = 10,995.09/100.87 - Step 6: Final answer
x = 109.00
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.