What is the equation of 21 less than 11 times a number results in seven times a number decreased by 29 what is the number

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

Including 6% sales tax, an inn charges $135.68 per night. find the inns nightly cost

Which equation is true? i. 56 ÷ 4·7 = 82 ÷ (11 + 5) ii. (24 ÷ 8 + 2)3 = (42 + 9)2 neither i nor ii ii only i and ii i only