Let 2x – y = 3 ——— equation 1
Let x + 5y = 14 ——— equation 2
Making x the subject in eqn 1, = x = y + 3 / 2 ——— eqn 3
• Put eqn 3 in eqn 2
(y + 3 / 2) + 5y = 14
6y = 14 – 3/2
6y = 25/2
y = 25/12
• put y = 25/12 in eqn 3
x = (25/12 + 3/2)
x = 43/12
Answer:
The correct answer to the question is
e. If is likely that between 35% and 41% percent of the driving population would be willing to pay higher gas prices to protect the environment.
Step-by-step explanation:
The margin of error expresses the number of percentage points of error is contained within survey result. A large error margin therefore reduces the level of dependence on a given statistic. The margin of error describes the expected variation between the statistic sample and the real population value.
In the question, the option
e. If is likely that between 35% and 41% percent of the driving population would be willing to pay higher gas prices to protect the environment , clearly depicts the definition of margin of error as it shows the expected variance from te real population
Answer:
Bobby around 131 minutes and Billy around 111 minutes
Step-by-step explanation:
To solve the problem it is important to raise equations regarding what happens.
They tell us that Billy (Bi) and Bobby (Bo) can mow the lawn in 60 minutes. That is to say that what they prune in a minute is giving as follows:
1 / Bo + 1 / Bi = 1/60 (1)
They say Billy could mow the lawn only in 20 minutes less than it would take Bobby, therefore
1 / Bi = 1 / (Bo-20) (2)
Replacing (2) in (1) we have:
1 / Bo + 1 / (Bo-20) = 1/60
Resolving
(Bo - 20 + B0) / (Bo * (Bo-20) = 1/60
120 * Bo - 1200 = Bo ^ 2 - 20Bo
Rearranging:
Bo ^ 2 - 140Bo -1200 = 0
Now applying the general equation
Bo = 130.82 or Bo = 9.17, <em>this last value cannot be because Billy took 20 minutes less and neither can he prune faster than the two together</em>, therefore Bobby only takes around 131 minutes and Billy around 111 minutes
Checking with equation 1:
1/131 +1/111 = ~ 1/60
Answer:
two-sixths of 24
Step-by-step explanation:
7<8
