59.

Let the number is N which when divide by 3,4 , 5 leaves reminder It means N+1 should divide by 3, 4 and 5
If the number is completely divide means it should be multiple of 3,4, and 5
N + 1 = 3 x 4 x 5 = 60
N = 60 - 1 = 59

The little boy used one $50, one $20, five $5's, two $2 bills and a one dollar bill.

0.5
0.5/0.5=1
Any number divided by itself equal to 1

The total number of toes is 5170.

The puppies: 4 children × 4 backpacks × 4 dogs × 4 puppies × 4 legs × 4 toes = 4096
Plus the dogs: 4 children × 4 backpacks × 4 dogs × 4 legs × 4 toes = 1024
Plus the children: 4 children × 2 legs × 5 toes = 40
Plus the driver of the school bus: 2 legs × 5 toes = 10
------- +
This gives the following total number of toes: 5170

4

x * 3 + 5 = 17 => x * 3 = 12 => x = 12 / 3 = 4

64

The series consists of squares and cubes of consecutive natural numbers i.e. 1^2, 1^3, 2^2, 2^3, 3^2, 3^3.
4^3 = 64.

20, 22, 24, 26

2n + (2n + 2) + (2n + 4) + (2n + 6) = 92
8n + 12 = 92 => 8n = 80 => n = 10
2n = 20

155 is the least number when divided by 36, 24 and 16 leaves 11 as remainder in each case.

Given numbers: 16, 24, 26

Finding LCM which is Lowest Common Factor is
LCM = 2 × 2 × 2 × 3 × 1 × 2 = 144

144 is the LCM of 36, 24 and 16.

Given condition leaving 11 as reminder

By adding 11 to LCM = 11+144 = 155

155 is the least number when divided by 36, 24 and 16 leaves 11 as remainder in each case.

6 because 10 divided by 2 is 5 then minus one from friend and add one from me and I have 6.

1.

30/45 of 144 = 6/9 x 144 = 96
19/57 of 96 = 1/3 x 96 = 32
12.5% of 32 = 4
17/68 of 4 = 1/4 x 4 = 1

27

X+Y=10
Y=10-X Use this to substitute for Y
X+Z=20
Z=20-X Use this to substitute for Z.
Y+Z=24 Substitute for Y and Z
(10-X)+(20-X)=24
30-2X=24
-2X=-6
X=3
X+Y=10 Put in value for X.
3+Y=10
Y=7
X+Z=20 Plug in value for X.

3+Z=20
Z=17
CHECK:
Y+Z=24
7+17=24
24=24
X+Y+Z=?
3+7+17=?
27=?
ANSWER: The sum X+Y+Z=27

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