The probability that the next 4 winners will all be 7th grade students is 3/4
Answer:
8
Step-by-step explanation:
0) the basic formula is: L=v*t, where L - distance, v - speed/velocity; t - time;
1) if the person's speed in still water is 'v' and the speed of water is 5 (according to the condition), then the upstream speed is 'v-5' and the downstream speed is 'v+5';
2) according to the condition the upstream time and the downstream time are the same, it means t₁=t₂=t, where t₁=upstream time and t₂=downstream time;
3) according to the items above it is possible to make up the equation of the upstream travel: t(v-5)=3; ⇒ t=3/(v-5);
4) according to the items above it is possible to make up the equation of the downstream travel: t(v+5)=13; ⇒ t=13/(v+5);
5) if t=3/(v-5) and t=13/(v+5), then

Answer:
I think is -x + 105/42y
Step-by-step explanation:
2(3/10)x - 5/7y - 4(5/6)y - 2(4/5)x
6/10x - 5/7y - 20/6y - 8/5x
6/10x - 8/5x - 5/7y - 20/6y
6-16/10x - 35+140/42y
-10/10x + 105/42y
-x + 105/42y
Answer: (1,4)
Explanation: The domain looks at the x coordinates and (1,4) is the only x coordinate in the range given (due to the bracket)
The given system of equation that is
and
has infinite number of solutions.
Option -C.
<u>Solution:</u>
Need to determine number of solution given system of equation has.

Let us first bring the equation in standard form for comparison


To check how many solutions are there for system of equations
, we need to compare ratios of 
In our case,



As
, so given system of equations have infinite number of solutions.
Hence, we can conclude that system has infinite number of solutions.