On a piano, the ratio of black keys to white keys is 9 to 13, if there are 88 keys on a piano how many are black?

36 black keys

Step-by-step explanation:

9(88-x)=13x

792-9x=13x

792=22x

x=36

Hope this helps: )

hey there!

12 is twice as much as 6 because 6 goes into 12 2 times.

since the rabbit is twice as tall, we should multiply the weight of the first rabbit, 0.25, by 2.

0.25 x 2 = 0.5

therefore, the 12 inch chocolate rabbit weighs 0.5 lb, or half a pound.

hope this !

in mathematics, a constraint is a condition of an optimization problem that the solution must satisfy. there are several types of constraints—primarily equality constraints, inequality constraints, and integer constraints. the set of candidate solutions that satisfy all constraints is called the feasible set.

hoped i'm right lol