<span>The area of the triangle with height 12 inches and the base of 5 inches is 30 square inches. The area (A) of a triangle with height, h, and base, b, is: A = h * b / 2. We know that h = 12 in and that b = 5 in. Therefore, the area of this triangle will be: A = 12 in * 5 in / 2 = 60 in^2 / 2 = 30 in^2. The area of the triangle is 30 square inches.</span>
Answer:
-23/5
Step-by-step explanation:
-3/5+(-8/2)
-3/5-4
-23/5
First we need to get some expressions:
"Four times the number of white marbles" = 4*w
"9 times the number of red marbles" = 9*r
"...exceeded...by 10": So 4*w is 10 more than 9*r or 4*w = 9*r +10
"ratio of blue marbles to red marbles is 3 to 1" : b/r = 3/1
b=3*r
"there is a total of 65 marbles": b+r+w=65
So our system becomes
b = 3*r
65 = b+r+w
4*w = 9*r+10
The first equation allows us to substitute immediately into the second equation so
65 = 4*r+w
however, we can divide the third equation by 4 to get w:
w = (9*r)/4+10/4
This can then be plugged into the second to get:
65 = 4*r+(9*r)/4+10/4 = (16*r)/4 + (9*r)/4+10/4 = (25*r+10)/4
260 = 25*r+10
250 = 25*r
r=10
Now we simply plug this result into the substitutions to get w and b:
w = 90/4+10/4 = 100/4 = 25
b=30
So there are 10 red marbles, 25 white marbles, and 30 blue marbles
Now it sounds like we should be picking some out at random ;)
Answer: b
Step-by-step explanation:
10 x 10= 100
15 x 10= 150
100+150= 250