Question

A recipe that serves two people calls for 1,600 milligrams of baking soda. You want to make enough for 10 people. How much baking soda do you need in grams

Answer 1

10/2=5
5 x 1600 = 8000 milligrams
               = 8 grams

Answer 2

Divide 10 by 2 because 1,600 milligrams of baking soda feeds 2 people. then multiply your quotient by 1,600.

( 10 / 2 = 5 )

5 is your quotient.
multiply 5 and 1,600

1,600 X 5 = 8,000

but you want grams.
there are 1,000 milligrams in a gram.
divide 8,000 by 1,000

8,000 / 1,000 = 8

you need 8 grams of baking soda to feed 10 people