Final answer:
The actual sales volume is 20 units.
Step-by-step explanation:
We can solve this problem using a proportion.
Let's assume that the actual sales volume is x.
We know that 170% of the sales volume is equal to 34 units, so we can set up the proportion:
170% / 100% = 34 / x
To solve for x, we can cross multiply and solve:
170x = 34 * 100
170x = 3400
x = 3400 / 170 = 20
Therefore, their actual sales volume is 20 units.