Finding the Fourth Proportional to 105.21, 156.78 and 99
Calculator
Solution
The fourth proportional to 105.21, 156.78 and 99 is: 147.53
Step by Step Solution
- Step 1: Write the proportion equation
105.21 : 156.78 = 99 : x - Step 2: Convert to fraction form
105.21/156.78 = 99/x - Step 3: Cross multiply
105.21x = 156.78 × 99 - Step 4: Simplify right side
105.21x = 15,521.22 - Step 5: Solve for x
x = 15,521.22/105.21 - Step 6: Final answer
x = 147.53
Related Problems
Find fourth proportional to 52.61, 78.39 and 49.50
Half scale
Find fourth proportional to 210.42, 313.56 and 198
Double scale
Find fourth proportional to 106.21, 158.27 and 100
Similar ratio
Find fourth proportional to 157.82, 235.17 and 148.50
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.