How many times smaller is 2 × 10-12 than 4 × 10-9?

=499,750,000,000

Step-by-step explanation:

2 × 10-12 =500000000000  

4 × 10-9=250000000

500000000000-250000000=499,750,000,000

I hope this helps (:

4 packs of water and 7 packs of candy bars

step-by-step explanation:

35x4=140

140/20=7

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: