March = -165
April = -156
In march he is negative MORE money, meaning he has MORE money in April
This question is trying to confuse you, ussually the lowest number means less, but these numbers are negative, so the lowest number means more.
He has the least amount of money in March
Answer: a - 4.512 hours
b - 1.94 hours
Step-by-step explanation:
Given,
a) A(t) = 10 (0.7)^t
To determine when 2mg is left in the body
We would have,
A(t) = 2, therefore
2 = 10(0.7)^t
0.7^t =2÷10
0.7^t = 0.2
Take the log of both sides,
Log (0.7)^t = log 0.2
t log 0.7 = log 0.2
t = log 0.2/ 0.7
t = 4.512 hours
Thus it will take 4.512 hours for 2mg to be left in the body.
b) Half life
Let A(t) = 1/2 A(0)
Thus,
1/2 A(0) = A(0)0.7^t
Divide both sides by A(0)
1/2 = 0.7^t
0.7^t = 0.5
Take log of both sides
Log 0.7^t = log 0.5
t log 0.7 = log 0.5
t = log 0.5/log 0.7
t = 1.94 hours
Therefore, the half life of the drug is 1.94 hours
Answer:
adult cost £7, child cost £2
Step-by-step explanation:
let a represent an adult and c a child , then
2a + 3c = 20 → (1)
a + 4c = 15 → (2)
Multiplying (2) by - 2 and adding to (1) will eliminate a
- 2a - 8c = - 30 → (3)
Add (1) and (3) term by term to eliminate a, that is
- 5c = - 10 ( divide both sides by - 5 )
c = 2
Substitute c = 2 into either of the 2 equations and evaluate for a
Substituting into (2)
a + 4(2) = 15
a + 8 = 15 ( subtract 8 from both sides )
a = 7
The cost of an adult ticket is £7 and a child ticket is £2
Answer: it says independent work
Step-by-step explanation:
$2 per notebook would be the correct answer