It is a knowledge check
On aleks
Answer:
36 laps Ronnie swim during practice .
Step-by-step explanation:
Let us assume that the laps that Ronnie swims be x .
Let us assume that the laps that Jackie swims be y .
As given
For every 3 laps that Jackie swims, Ronnie swims 4 laps.
i.e
3 × laps that Ronnie swims = 4 × laps that Jackie swims
3 × x = 4 × y
3x = 4y
Equation becomes
x + y = 63
Thus by using 3x = 4y .

Thus

4x + 3x = 63 × 4
7x = 252
x = 36
Put the value of x in the equation x + y = 63
36 + y = 63
y = 63 - 36
y = 27
Therefore the 36 laps Ronnie swim during practice .
Answer:
<u>z = -4</u>
Step-by-step explanation:
<u>Given</u> :
- x = -2
- y = -5
- z divides xy in the ratio 2 : 1 (m : n)
<u>Solving</u> :
- Take the section formula
- z = [my + nx] / [m + n]
- z = [2 x -5 + 1 x -2] / [2 + 1]
- z = -10 - 2 / 3
- z = -12 / 3
- <u>z = -4 </u>
Find the deviation they each hae from the mean
250+the deviations=x
265 is -15 less than 250
-15
264 is -14 less than 250
-14
228 is 22 less than 250
22
add them
-15-14+22=-7
250-7=243=x
it is less than 250
answer is A
value of x=243