## Bossvideogamer21 one year ago do i cross cancel using division?

1. Bossvideogamer21

here is the problem: Scientists can estimate the amount of bacteria in a refrigerated food by using the formula 0.2b=T^2/20 where b is the number of bacteria and t is the number of seconds. What is the approximate time a food was in the refrigerator if there are 625 bacteria?

2. hartnn

$$0.2 \times 625 = T^2/ 20 \\ \implies T^2 = 0.2 \times 625 \times 20 = ....$$

3. hartnn

so in which step you had that doubt?

4. Bossvideogamer21

i did everthing right except setting up the problem

5. hartnn

so we just plug in b = 625 in the given formula and multiply both sides by 20

6. hartnn

to eliminate the fraction (division by 20) on right

7. Bossvideogamer21

i got everything except the divide by 20 part

8. Bossvideogamer21

so is this right : in seconds the answer is 2,500 and in minutes the answer is 41.6

9. hartnn

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10. hartnn

T^2 is 2500 so T = 50 seconds :)