Q: How many 2s in 50?

Write your answer...

2r + 2s = 50 2r - s = 17 therefore 4r - 2s = 34 Add so that you can eliminate one of the variables: 2r + 2s = 50 4r - 2s = 34 ---------------- 6r + 0s = 84 Solve for r: 6r = 84 r = 14 Substitute r into one of the original equations: 2(14) + 2s = 50 28 + 2s = 50 2s = 22 s = 11 Doublecheck with the other original equation: 2(14) - 11 = 28 - 11 = 17

4

3 x (22)2 + 2 = 50

310.

1

unknown

36

20 of them.

33

1

26

46.

26 - 6*2 - 2 = 64-12-2 = 50

2, 4 8, 16, and 32.

100 2s for the hundreds digit of 200-30010 2s for the tens digit of 220-23010 2s for the ones digit of 200-300________________________________120 '2s'

2

39

It has 17 of them with a remainder of 1

Exactly 18 of them

240 ÷ 2 = 120

Exactly 16

5,0 moles (NH4)2S contain 60,22140857.10e23 ammonium ions.

6+6=12, x2=24, x2=48, +2 is 50

150 g x 1 mol/68.154 g = 2.2 moles (2 sig figs)

The compound (NH4)2S is ammonium sulfide.