30% decrease
175 divided by 250 = 0.7
1 - 0.7 = 0.3
0.3 = 30%
Answer: 9+4n-1 = 20
We can solve this by substitution.
Replace n with the value given, 3 (remember 4n means 4 times n):
9 + 4*3 - 1
Then work it out using arithmetic
9+12-1
=20
Hello from MrBillDoesMath!
Answer: The expressions are equal by the distributive law of number.
Thank you,
MrB
They call it the Whirl Series ^.^