What is 30% of 255? and how did you get to that answer?

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?

The nth term of a sequence in 2n-1 the nth term of a different sequence is 3n+1 work out 3 numbers that are in bothe sequences and are between 20 and 40