Answer:
b. 98
Step-by-step explanation:
May and June:
May: 223 Dinztop sales
June: 148 Dinztop sales.
So

In June, it sold 0.6637 = 66.37% the amount of computers sold in May.
How many Dinztop computers will be sold in July?
Because of the same percent rate, 0.6637 = 66.37% of the amoutns sold in June.
0.6637*148 = 98
The correct answer is given by option b.
Try, please, this:
1) Imagine, that pharmacist used 'x' gr. of 40% solution and 'y' of 70% solution.
Together (20 gr. of 52% sol.) it will be x+y=20.
2) From other side, the pharmacist combined 40x and 70y gramms, after obtaining together it is 52(x+y) gramms. In other words 40x+70y=52(x+y)
3)

Answer: 8 gr. of 70% solution and 12 gr. of 40%.
Round 8.1 down to 8
Round 4.2 down to 4
8(4)= 32
The estimated product is 32.
Hope this helps!