Finding the Fourth Proportional to 212.91, 319.55 and 84.75
Calculator
Solution
The fourth proportional to 212.91, 319.55 and 84.75 is: 127.20
Step by Step Solution
- Step 1: Write the proportion equation
212.91 : 319.55 = 84.75 : x - Step 2: Convert to fraction form
212.91/319.55 = 84.75/x - Step 3: Cross multiply
212.91x = 319.55 × 84.75 - Step 4: Simplify right side
212.91x = 27,081.44 - Step 5: Solve for x
x = 27,081.44/212.91 - Step 6: Final answer
x = 127.20
Related Problems
Find fourth proportional to 106.46, 159.77 and 42.38
Half scale
Find fourth proportional to 425.82, 639.09 and 169.50
Double scale
Find fourth proportional to 213.91, 321.05 and 85.75
Similar ratio
Find fourth proportional to 319.37, 479.32 and 127.13
1.5x scale
Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.