Divide 110 into two parts so that one will be 150 per cent of the other. What are the 2 numbers?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

If 21x = 79x, what is the value of x?