Answer:
7 is not a solution for x.
Step-by-step explanation:
To see if 7 is a solution for x, we will simply plug in the value for x and see if the left hand side is equal to the right hand side.
3x + 8 - x = 57 - 4
3(7) + 8 - (7) ?= 57 - 4
21 + 8 - 7 ?= 53
29 - 7 ?= 53
22 ?= 53 (( NO ))
Since 22 does not equal 53, 7 is not a solution for x.
Let's find the solution for x:
3x + 8 - x = 57 - 4
2x + 8 = 53
2x = 45
x = 22.5
Let's validate this solution for x:
3x + 8 - (x) = 57 - 4
3(22.5) + 8 - (22.5) ?= 57 - 4
67.5 + 8 - 22.5 ?= 53
45 + 8 ?= 53
53 == 53 (( YES ))
Since 53 is indeed equal to 53, then 22.5 is a solution for x.
Cheers.
Answer:
The answer tot he question provided is 25.
Answer:
What we know is that 30% of the group have brown hair and are girls. It means that in the other 70% we have the boys with brown hair, the other boys and the other girls.
In the case all the girls have brown hair, the 70% remaining would be boys. So 70% of then would have brown hair. (0.7*0.7=0.49 -> 49% of the children would be brown hair) so 49% (boys) and 30% (girls) are more than 50%..
Now, let's suppouse that 90% of the group are girls. It means 10% are boys and 70% of that 10% (=7%) are the boys in the group that have brown hair. Now 7% + 30% of the children have brown hair, wich isn't more than the half.
We have explained with two extreme cases that the information is not enough for making a precise answer