A culture of a certain bacteria doubles every hour. At 9:00 a.m, there were already 120 bacteria. Which equation represents the number of bacteria, n , at 8:00 a.m? How many bacteria were there?(1 point)

Question

Responses

2n=120; at 8:00 a.m., there were 240 bacteria.
2 n equals 120 ; at 8:00 a.m., there were 240 bacteria.

n2=120; at 8:00 a.m., there were 240 bacteria.
Start Fraction n over 2 End Fraction equals 120 ; at 8:00 a.m., there were 240 bacteria.

n2=120; at 8:00 a.m., there were 60 bacteria.
Start Fraction n over 2 End Fraction equals 120 ; at 8:00 a.m., there were 60 bacteria.

2n=120; at 8:00 a.m., there were 60 bacteria

Answer 1

2n=120; at 8:00 a.m., there were 240 bacteria.

Answer 2

5 of 55 of 5 Items
Question
A survey is conducted in a certain neighborhood to find out residents’ favorite vacation spot. Two-fifths of the respondents, or 80 residents, said they like spending their vacation at the beach. Which equation represents the number of residents, r, surveyed? How many residents were surveyed?(1 point)
Responses

25r=80; 32 residents were surveyed.
Start Fraction 2 over 5 End Fraction r equals 80 ; 32 residents were surveyed.

52r=80; 200 residents were surveyed.
Start Fraction 5 over 2 End Fraction r equals 80 ; 200 residents were surveyed.

25r=80; 200 residents were surveyed.
Start Fraction 2 over 5 End Fraction r equals 80 ; 200 residents were surveyed.

80r=25; 200 residents were surveyed.

Answer 3

Start Fraction 2 over 5 End Fraction r equals 80 ; 32 residents were surveyed.