Answer:
7/40
Step-by-step explanation:
There are 3 girls+9 boys = 12 students in the 7th grade
P (girl in 7th grade) = girls/ total
= 3/12 = 1/4
There are 7 girls+3 boys = 10 students in the 8th grade
P (girl in 8th grade) = girls/ total
= 7/10
P(7th grade girl, 8th grade girl) = 1/4 * 7/10 = 7/40
uhh well 4 + 2 is 6- and it's in brackets so that's a start?
there's nothing between the brackets and the number
division: 3
multiplication: 12
addition: 8
subtraction: 4
expansion: 2(2+4) = 12
Step-by-step explanation:
let jon age be x
dad age is 2 of x i.e 2x
grandpa age is 7 + 3(x)
The sum of jon dad and grandpa age is 145 i.e
x + 2x + (7+3x) = 145
3x +. 7 + 3x = 145
6x = 145- 7
6x = 138
divide both sides by 6
x = 23
jon age is 23
while
grandpa age is
7 + 3(x)
7 + 3(23)
7 + 69
76.
The three items cost altogether is : 111.32 + 28.75 + 73.21 = 213.28
So, he must work 213.28 : 8.75 = 24.3748571429...
Since if he works 24 hours, he wouldn't have enough money to buy the 3 items, so he must work 24 + 1 = 25 hours.
Recheck : 25 x 8.75 = 218.75 ( > 213.28)
Option C and D is correct .....
