Ateacher has 3 hours to grade all the papers submitted by the 35 students in her class. she gets through the first 5 papers in 30 minutes. how much faster does she have to work to grade the remaining papers in the allotted time? will it be wrong if i say '' she has to be 1.2 times faster instead of 20% faster? ''

Let us calculate the teacher's initial speed. It can be calculated as thus:

She does 5 papers in 30 minutes. Thus means her speed is 6 minutes per paper (Because minutes per paper).

Now, if the teacher has to complete the remaining 30 papers in the remaining 150 minutes (2 hours 30 minutes=120+30=150 minutes), she will have to go through one paper in minutes. Thus, her speed now will have to be 5 minutes per paper.

Now, we know that 1.2 times 5=6. Therefore, it will not be wrong to say that '' she has to be 1.2 times faster instead of 20% faster" because both mean the same.

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2