If the half life is 20 minutes, then in 40 minutes there is 2 half lives. At the end of Each half life, you will have 1/2 of the sample remaining. So...
After 20 min you have
960/2 = 480
After 40 minutes you will have
480/2 = 240 grams
Answer:
196
Step-by-step explanation:
1+2+3+4+......+25+26+27 = (1+27) + (3+25) + (5+23)+(7+21) + (9+19) + (11+17) + (13+15)
= 28 x 7 = 196
It's like area of trapezoid of bases: 1, 27 and height of 14
8:50 am
1/3 of 30 = 10 min (so it takes 10 min for him to drive to work)
9:00-10min = 8:50
Lets start from scratch.
45 is the number of money she spent that means that right side of = sign is 45
let m represents number of roses.
we can write:
t*$1+ m*$2 = $45
Since she bought 3 more tulips than roses that means that m = t - 3
when we express m we get:
t + 2*(t-3) = 45
the answer is B.
