Answer:
35
Step-by-step explanation:
Here we see 5 black keys for every 7 white keys.
So the ratio is 5:7
If we need 49 white keys, find the amount we scale the original ratio by:
49/7 = 7
So we are scaling by a factor of 7.
The number of black keys would be 5 * the scale of 7. = 35
So there should be 35 black keys.
Answer:
B
Step-by-step explanation:
The answer is b, because if 5 and 10 are in the middle, you add them (15) then divide by 2, to get 7.5
Answer:
0.4
Step-by-step explanation:
1.6 - 1.2 = 0.4
Answer:
12
Step-by-step explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
a^2 + 9^2 = 15^2
a^2 +81 =225
Subtract 81 from each side
a^2 = 225-81
a^2 = 144
Take the square root of each side
sqrt(a^2) = sqrt(144)
a=12
The answer would be -9
I hope this helps.