Answer:
(b) 26.6 days
Step-by-step explanation:
Half life, T = 4 days
initial amount, No = 100 mg
(a) The exponential function is given by

where, N is the amount left.
(b) N = 1 mg

Answer:
D: 11
Step-by-step explanation:
4(x + 2) - 17 = 35
4x+8 - 17=35
4x-9=35
4x=35+9=44
x=44/4=11
Answer: £ 81.38
Step-by-step explanation:
Given: On Monday,
5 builders took
hours ( i.e.
hours ) to build a wall.
On Tuesday, only 2 builders were available.
As workers are inversely proportional to the time if the job remains constant.
Inverse variation equation : 
Let x be the time taken by 2 builders, then


So, 2 builders will take 8.75 hours.
Each paid £9.30 for each hour.
Then, each builder will be paid for the work completed on Tuesday = £9.30 x 8.75
≈ £ 81.38
Hence, each builder will be paid £ 81.38 for the work completed on Tuesday .
11,513 is the answer I really don't know how to write it all out sorry
Answer:
x = 4; y = 8
Step-by-step explanation:
y=2x
y=x+4
2x = x + 4
x = 4
y = 2x = 2(4)
y = 8
Solution: x = 4; y = 8