Answer:it is D)172 in the khan academy answers
Step-by-step explanation:
Since if he gets the driveway done in 20 minutes he gets 1/20th of the driveway done in 1 minute (if x=20 then x/20=1 by dividing both sides by 20) and if his brother gets 1/12th of the driveway done in one minute, then if t represents the time it takes to shovel the driveway, t/20+t/12=1 driveway shoveled as 1/20+1/12=amount they can do in 1 minute, so t/20+t/12 is how much they can do in t minutes. Multiplying both sides by 20*12=240, we get 12t+20t=32t=240. Dividing both sides by 32, we get 240/32=7.5 minutes to shovel the driveway.
Answer:
-0.05
Step-by-step explanation:
Given the expression :
0.1×( – 0.9+ – 0.2÷ – 0.5)
Evaluating the bracket :
0.1 * (-0.9 - 0.2 ÷ - 0.5)
Solving the division first
-0.2 ÷ - 0.5 = 0.4
Now we have ;
0.1 * (-0.9 + 0.4)
0.1 * - 0.5
= - 0.05
Answer:
Hello the answer to your question is 0.4 sec.
Step-by-step explanation:
Hope this helps
