Mrs. Black’s class participated in a bike challenge to raise money for new computers in the library. How many students completed less than 8 miles for the challenge?
3 dots on 0,
2 dots on 2,
3 dots on 4,
1 dot on 6,
4 dots on 8,
3 dots on 12,
1 dot on 14 and
2 dots on 16 is given.
A.19 students
B.9 students
C.6 students
D.4 students

A The correct answer is A

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -