If 50% of a number is 170, that means the number must be double 170 (170 times 2)
And 170 multiplied by 2 is 340.
Therefore, the number is 340. Now we have to find 70% of 340.
We can do that by: taking 340 times 0.70
So 340 times 0.70 is..
238
Hope that helped!