Solution:

186

Explanation :
21+11*1 => 32
32+11*2 => 54
54+11*3 => 87
87+11*4 => 131
131+11*5 => 186

Solution:

Ready for anything

Solution:

4

92 - 38 = 54
5 is given and 4 is missing

Solution:

A Stoplight

Solution:

4

6*3 equals 18
7*9 equals 63
6*4 equals 24
7*6 equals 42, ? should be replaced by 4.

Solution:

Horse And queen are chess pieces

Solution:

6

sum of opposite number is 21

Solution:

Amelia --> vanilla-shake
Charlotte --> chocolate-shake
Evelyn --> strawberry-shake
Anna --> burger
Ella --> curd

Solution:

4 years

issabella : 4 years old.
sophie : 10 years old

Explanation : issabella is 'I' and sophie is 'S'

equation 1 : 2/5 S = I
equation 2 : (S+2)= 2(I+2)
equation 2 : (S-2)= 4(I-2)
Solve above equation

equation 1: 2/5 of 10 is 4
equation 2: (4+2) is half of (10+2)
equation 3: (4-2) is one-forth of (10-2)

Solution:

Bad Intention (BAD in TENTION).