Explanation

Use the set formula: 

Students who study CS or Math = CS + Math - Both  

= 55 + 50 - 10  

= 95 students

Students who study neither = Total students - Students who study CS or Math  

= 100 - 95  

= 5 students

Last verified on 02-09-2026

Explanation

SISTER = 535301

S = 5, I = 3, T = 3, E = 0, R = 1

UNCLE = 84670

U = 8, N = 4, C = 6, L = 7, E = 0 (E = 0 matched)

BOY = 129

B = 1, O = 2, Y = 9

Now SON

S = 5

O = 2

N = 4

SON = 524

Last verified on 20-10-2026

Explanation

Logic: +4

B = 2nd letter

F = 6th letter (2+4)

J = 10th letter (6+4)

N = 14th letter (10+4)

Next = 14+4 = 18th letter = R

Last verified on 11-10-2026

Explanation

• The series alternates between subtracting 1 and adding 2:
  • 12 → 11 (subtract 1)
  • 11 → 13 (add 2)
  • 13 → 12 (subtract 1)
  • 12 → 14 (add 2)
  • 14 → 13 (subtract 1)

Following this alternating pattern, the next step should be adding 2 to 13:

$$13 + 2 = 15$$

Last updated by NA on 06-11-2026

Explanation

The prime numbers between 60 and 80 are:

61, 67, 71, 73, and 79

Let's add them up:

61 + 67 = 128

128 + 71 = 199

199 + 73 = 272

272 + 79 = 351

Last updated by NA on 05-11-2026