Answer:
217
Step-by-step explanation:
62x3=186+ .5 of 62 which is 31
186+31=217
A half-life of the isotope is 15 days and at start its mass is 32 g.
A table:
t: m:
0 32 g
15 16 g
30 8 g
45 4 g
60 2 g
75 1 g
In the first column is used an arithmetic sequence ( a 1 = 0, d = 15 ).
In the second column is used a geometric sequence ( a 1 = 32, r = 1/2 )
that would be 3 minutes and 45 seconds (:
Answer:
$7.20
Step-by-step explanation:
If 8 pens cost $3.84, we need to find out how much ojne pen costs.
To find out the cost of one pen we need to divide $3.84 by 8.
$3.84 / 8 = $0.48
1 pen cost $0.48
We then need to work out the cost of 15 pens. So from using the information that one pen costs $0.48 we can multiply that by 15 to find out the answer.
$0.48 x 15 = $7.20
15 pens cost $7.20
