The answer is: 91 . There are many methods to solve it . If you take the fourth colomn you will find the differances between (15 & 28) -( 28& 45) -(45&66) are 13 & 17 & 21 , so the last differance will be 25. If you add 25 to 66 the total must be 91 .I think that it’s a sequence .I took less than one minute.

the answer is 91
why?
in the mentioned row we added 13 to the secound number ‘ 17 to the third’
21 to the fourth and so we have to add21 to the number 66 so the number are must be 91

91

less then a minute

A.(2+3)*5=15,b.((3+4)*4=28,c.(4+5)*5=45,d.(5+6)*6=66,e.(7+6)*7=91

12×2=24+4 =28

20×2=40+5=45

30×2=60+6=66

42×2=84+7=91 (answer)

91

91. The relation in second column third column.

Just add 1,2 3,4 and 5 in third column figure and multiply with second column figure

91

It is (8 x 7 = 56) + (7 x 5 = 35) = 91

It’s 91

All the numbers go up by additional 4 to the difference. 13; 17; 21. So the next will be 25 which is added to 66 giving a result of 91.

See the 4th column

15+13=28

28+17=45(13 is increased by 4)

45+21=66(21 is increased by 4)

66+25=91(25 is increased by 4)

so correct answer is 91

good

91 i.e 15+13=28, 28+17=45, 45+21=66, & 66+25=91 just add 4 to every next step so simple dont confuse with table

(13*56)/8=91

91

91

91

great I got the answer to be 91 within one minute

91 ^_^

The answer is: 91 . There are many methods to solve it . If you take the fourth colomn you will find the differances between (15 & 28) -( 28& 45) -(45&66) are 13 & 17 & 21 , so the last differance will be 25. If you add 25 to 66 the total must be 91 .I think that it’s a sequence .I took less than one minute.

91 within less than thirty seconds.

it is 91, but by:

12 x 2 – (9) = 15

20 x 2 – (12) = 28 and so on.

the answer is 77 but what is the correct answer?

91 is the correct answer

The answer is 77

91 is the answer

91 in 30 sec

It’s 91. As explained by Mr.Shaukat. Got it after a seond attempt, unfortunately.

3×5=15

4×7=28

5×9=45

6×11=66

7×13=91

91

91

Answer is 91

Answer is 91

equation

x4=(x1+x2)*x2

x5=x2*x3

1st Row: 2+3=5X3=15

2nd Row:3+4=7X4=28

3rd Row:4+5=9×5=45

4th Row:5+6=11X6=66

5th Row:6+7+13X7=91 (Answer)

91

91

91

There are many ways to get the results. almost all methods have been used by viewers. Congratulations. Its also an old quiz.

the answer is 91

why?

in the mentioned row we added 13 to the secound number ‘ 17 to the third’

21 to the fourth and so we have to add21 to the number 66 so the number are must be 91