Finding the Fourth Proportional to 114, 171 and 90
Calculator
Solution
The fourth proportional to 114, 171 and 90 is: 135
Step by Step Solution
- Step 1: Write the proportion equation
114 : 171 = 90 : x - Step 2: Convert to fraction form
114/171 = 90/x - Step 3: Cross multiply
114x = 171 × 90 - Step 4: Simplify right side
114x = 15,390 - Step 5: Solve for x
x = 15,390/114 - Step 6: Final answer
x = 135
Related Problems
Find fourth proportional to 57, 85.50 and 45
Half scale
Find fourth proportional to 228, 342 and 180
Double scale
Find fourth proportional to 115, 172.50 and 91
Similar ratio
Find fourth proportional to 171, 256.50 and 135
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.