Respuesta :

Answer:

Step-by-step explanation:

If you wanna decrease the number 10 by 90%, It's just 9. You simply need to multiply a/100 at the number you try to decrease by a%.

Answer:

Decrease 20g by 90%: final value 2 gm

Step-by-step explanation:

decrease 90%: decrease 20 * 0.9 = 18

new value after decrease: 20 - 18 = 2