ANSWER:

Recall that a number is divisible by 4 if the two-digit number formed by the tens and ones digits is divisible by 4. Using the digits 1, 2, 3, 4 and 5, the following two-digit multiples of four can be formed: 12, 24, 32 and 52. There are 5 × 4 = 20 permutations of two digits chosen from the digits 1, 2, 3, 4 and 5. Therefore, the probability that the five-digit number is divisible by 4 is 4/20 = 1/5.

113 = 2 x 7² + 2 x 7¹ + 1 x 7⁰ = 221₇

(How can I get those number?

CLUE: Keep dividing 113 by 7:

113 \(\div\) 7 = 16 (remainder 1)

16 \(\div\) 7 = 2 (remainder 2)

Because 2  \(\div\) 7 = 0, we stop here.

We get three number: 2, 2, 1)

75 oranges

need 75 fruit

aaaaa

i will you to make this topic :)
replace x=1 into the polution above , we have 
p+4q=161 
=> q= (161-p)/4 
=> q=40-(p-1)/4 => q<40(1)
because the p and q are primes so (p-1) divisible for 4 =>p-1 >=4 => p>=5 (2)
Merged (1) with (2) we have q ={2;3;5;7;11;13;17;19;23;29;31}
then you try to the each of case : it will have 2 cases (correct satisfies) 
this case p=37 <=> q=31 and p=133 <=> q=7

i will you to make this topic :)
replace x=1 into the polution above , we have 
p+4q=161 
=> q= (161-p)/4 
=> q=40-(p-1)/4 => q<40(1)
because the p and q are primes so (p-1) divisible for 4 =>p-1 >=4 => p>=5 (2)
Merged (1) with (2) we have q ={2;3;5;7;11;13;17;19;23;29;31}
then you try to the each of case : it will have 2 cases (correct satisfies) 
this case p=37 <=> q=31 and p=133 <=> q=7 

30 percent :)

\(A=3+3^2+3^3+3^4+...+3^{99}+3^{100}\)

\(=3\left(3+1\right)+3^3\left(3+1\right)+...+3^{99}\left(3+1\right)\)

\(=\left(3+1\right)\left(3+3^3+...+3^{99}\right)⋮4\)

ok thank

I don't see the picture :V :V :V 

Ok, I agree.

We have :

1 minute : 155 people gained.

1 day : x people gained.

We have : 1 day = 1440 minutes.

So at the rate 155 people/1 minute, there are \(155\cdot1440=223200\) more people on Earth every day.

Everyday have 24h; a hour have 60minutes

=> Everyday have:

24 . 60 = 1440 [minutes]

So everyday, there are more people on Earth are:

1440 . 155 = 223 200 [people]

So everyday, there are more 223 200 people on Earth