Finding the Third Proportional to 810 and 990
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Solution
The third proportional to 810 and 990 is: 1,210
Step by Step Solution
- Step 1: Write the proportion equation
810 : 990 = 990 : x - Step 2: Convert to fraction form
810/990 = 990/x - Step 3: Cross multiply
810x = 990 × 990 - Step 4: Simplify right side
810x = 980,100 - Step 5: Solve for x
x = 980,100/810 - Step 6: Final answer
x = 1,210
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Why These Related Problems?
These problems maintain the same ratio (1.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.