Finding the Fourth Proportional to 660.68, 988.18 and 642.99
Calculator
Solution
The fourth proportional to 660.68, 988.18 and 642.99 is: 961.73
Step by Step Solution
- Step 1: Write the proportion equation
660.68 : 988.18 = 642.99 : x - Step 2: Convert to fraction form
660.68/988.18 = 642.99/x - Step 3: Cross multiply
660.68x = 988.18 × 642.99 - Step 4: Simplify right side
660.68x = 635,388.25 - Step 5: Solve for x
x = 635,388.25/660.68 - Step 6: Final answer
x = 961.73
Related Problems
Find fourth proportional to 330.34, 494.09 and 321.50
Half scale
Find fourth proportional to 1,321.35, 1,976.36 and 1,285.98
Double scale
Find fourth proportional to 661.68, 989.67 and 643.99
Similar ratio
Find fourth proportional to 991.01, 1,482.27 and 964.49
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.