Answer:
6.11km/hr
Step-by-step explanation:
Let the speed that Kelli swims be represented by Y
Speed of the river = 5km/hr
Distance = Speed × Time
Kelli swam upstream for some distance in one hour
Swimming upstream takes a negative sign, hence:
1 hour ×( Y - 5) = Distance
Distance = Y - 5
She then swam downstream the same river for the same distance in only 6 minutes
Downstream takes a positive sign
Converting 6 minutes to hour =
60 minutes = 1 hour
6 minutes =
Cross Multiply
6/60 = 1/10 hour
Hence, Distance =
1/10 × (Y + 5)
= Y/10 + 1/2
Equating both equations we have:
Y - 5 = Y/10 + 1/2
Collect like terms
Y - Y/10 = 5 + 1/2
9Y/10 = 5 1/2
9Y/ 10 = 11/2
Cross Multiply
9Y × 2 = 10 × 11
18Y = 110
Y = 110/18
Y = 6.1111111111 km/hr
Therefore, Kelli's can swim as fast as 6.11km/hr still in the water.
Answer:
Cluster sampling.
Step-by-step explanation:
Samples may be classified as:
Convenient: Sample drawn from a conveniently available pool.
Random: Basically, put all the options into a hat and drawn some of them.
Systematic: Every kth element is taken. For example, you want to survey something on the street, you interview every 5th person, for example.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. However, then only some elements of the group are surveyed.
In this question:
People divided into groups, by households.
Each member of the households(group) is surveyed, so cluster sampling.
<em><u>Question:</u></em>
The equations in this system were added to solve for x. What is the value of x? -2x+y=8 5x-y=-5 3x=3
Options:
x = negative 3
x = negative 1
x = 1
x = 3
<em><u>Answer:</u></em>
The value of x is 1
<em><u>Solution:</u></em>
<em><u>Given system of equations are:</u></em>
-2x + y = 8 ------- eqn 1
5x - y = -5 ------- eqn 2
The above equations are added to solve for "x"
Add eqn 1 and eqn 2
-2x + y + 5x - y = 8 - 5
Combine the like terms
-2x + 5x + y - y = 3
Add the like terms
3x + 0 = 3
3x = 3
Divide both sides of equation by 3
x = 1
Thus the value of x is 1
Answer:
78 Ft. ^2
Step-by-step explanation:
Cut it into two pieces, 6x2, and (15-9)x11, and solve.
1. 12
2. 66
Add: 66+12= 78!
I pretty sure you either add or subtract to get the answer