Algebraic equalities and formulas
Answers are for parents and teachers.
1
A pipe delivers 25 l of water per minute. By V = vt, how many litres flow in 12 minutes?
300
2
By the odd-number formula n = 2k - 1, find n for k = 9.
17
3
Express a from the formula P = 2(a + b).
a = P : 2 - b
4
Show with a formula that the sum of the consecutive natural numbers n and n + 1 is always odd.
n + (n + 1) = 2n + 1, which has the form of an odd number.