Finding the Fourth Proportional to 79.31, 118.28 and 78.12
Calculator
Solution
The fourth proportional to 79.31, 118.28 and 78.12 is: 116.50
Step by Step Solution
- Step 1: Write the proportion equation
79.31 : 118.28 = 78.12 : x - Step 2: Convert to fraction form
79.31/118.28 = 78.12/x - Step 3: Cross multiply
79.31x = 118.28 × 78.12 - Step 4: Simplify right side
79.31x = 9,240.23 - Step 5: Solve for x
x = 9,240.23/79.31 - Step 6: Final answer
x = 116.50
Related Problems
Find fourth proportional to 39.66, 59.14 and 39.06
Half scale
Find fourth proportional to 158.63, 236.57 and 156.24
Double scale
Find fourth proportional to 80.31, 119.77 and 79.12
Similar ratio
Find fourth proportional to 118.97, 177.42 and 117.18
1.5x scale
Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.