Finding the Third Proportional to 641 and 1,390
Calculator
Solution
The third proportional to 641 and 1,390 is: 3,014.20
Step by Step Solution
- Step 1: Write the proportion equation
641 : 1,390 = 1,390 : x - Step 2: Convert to fraction form
641/1,390 = 1,390/x - Step 3: Cross multiply
641x = 1,390 × 1,390 - Step 4: Simplify right side
641x = 1,932,100 - Step 5: Solve for x
x = 1,932,100/641 - Step 6: Final answer
x = 3,014.20
Related Problems
Find third proportional to 320.50 and 695
Half scale
Find third proportional to 1,282 and 2,780
Double scale
Find third proportional to 643 and 1,394
Similar ratio
Find third proportional to 961.50 and 2,085
1.5x scale
Why These Related Problems?
These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.