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:

125874 => 251748

251748 is twice the 125874 and have same digits 1,2,4,5,7 & 8

Solution:

Bad Intention (BAD in TENTION).

Solution:

-4

298 less 209 is 89
209 less 129 is 80
129 less 58 is 71
58 less -4 is 62
The result of each subsequent equation is 9 less than the previous one.

Solution:

A B C
E F G H
I J K L
M N O P
R S T
5 horizontal rows
4 vertical columns
4 diagonals with slope 1 (ROL, NKH, MJG, IFC)
4 diagonals with slope -1 (SNI, TOJE, PKFA, LGB)
2 knight's move diagonals with slope -2 (AJS, BKT)

Solution:

White should move the rook from
A1 to D1 and hence complete the castling move.

Solution:

G = 'Roger Federer'
H = 'Rafael Nadal'

#A spoke the truth and the rest lied.

Solution:

work in progress

Solution:

40

Solution:

None

The sum of numbers from 0-9(0,1,2,3,4,5,6,7,8,9) is 45 and therefore can be divisible by 3 and 9.

Solution:

Four

three placed flat on the table in a triangle(touching each other) and put the fourth one on top of them in the middle.

Solution:

Toy3 Toy6 | Toy1 Toy7 | Toy2 Toy5 Toy8 | Toy4

Solution:

5 minutes

Solution:

First come, first served

Solution:

0! or cos(0)

Solution:

2024

Seven occurrence
24-01-24
12-02-24
08-03-24
06-04-24
04-06-24
03-08-24
02-12-24

Solution:

13 x 3 + 1 = 40

The number of decks is absolutely not relevant here which means whether we mix 5 or 500 cards still results would be same.
Any card drawn will be a Ace,2,3,4,5,6,7,8,9,10,Jack,Queen or King, so there are 13 possibilities each time a card is drawn.
If you are lucky just 5 cards of the same kind can be obtained in 4 steps

The unluckiest(worst) way is our solution as we need to guarantee a four of a kind.
Draw 3 of each kind =>now we have 39 cards. Next card will guarantee 4 of a kind.

Solution:

30,450 miles.

Explanation:
For each 5 miles driven using this rotation, each tire will lose (2/29000)+(2/21000) of its tread.So, suppose we drive 5*N miles like this. Then, each tire will lose 2*N*((1/29000)+(1/21000)) of its tread. We wish to determine N so that the latter expression gets to be 1, representing all of each tire's tread. That happens when N=6090, which is when 5*N (the total miles driven) is 30,450.

Solution:

18