Answer:
86
Step-by-step explanation:
Given that there are 30 students in class 10R and the mean marks for the entire class was 70%. Therefore, total mark of class = 70 x 30 = 2100
Given that there are 20 boys in the class and the mean marks for the boys was 62 %. Therefore, total mark of boys = 62 x 20 = 1240
To calculate the mean mark for the girls we need to find the total number of girl and total mark of girls. total number of girl = 30 - 20 (boys) = 10 total mark of girls = total mark of class - total mark of boys = 2100 - 1240 = 860 mean mark for girls = 860 / 10 = 86
Answer:48
Step-by-step explanation:
Answer:
A system of linear equations is just a set of two or more linear equations. In two variables (x and y) , the graph of a system of two equations is a pair of lines in the plane. ... The lines intersect at infinitely many points.
Step-by-step explanation:
i hope this helped
A) x -y = 4
B) x + y = 30
x = 4 + y So,
B) 4 + y + y =30
2 y = 26
y = 13
x = 17
Answer:
14.2 years
Step-by-step explanation:
The multiplier of the population each year is 1 +5% = 1.05, so after n years the population has been multiplied by 1.05^n. You want to find the value of n that makes this expression equal to 2:
2 = 1.05^n
log(2) = n·log(1.05) . . . . . take logarithms
log(2)/log(1.05) = n ≈ 14.2
Growing at a rate of 5% per year, it will take about 14.2 years for the population to double.