A, because: 20x10 1/2=210
And 20x11 1/4=225
And 225-210=15
So thats the answer.
If the ratio of red marbles to blue marbles in a jar is 3 to 8, the meaning is for every 3 red marbles there are 8 blue marbles.
3 red marbles------------------8 blue marbles.
ratio=3/8
we have 40 blue marbles; we have to compute the number of red marbles.
1) Method 1; by the rule three.
3 red marbles-----------------8 blue marbles
x----------------------------------40 blue marbles
x=(3 red marbles * 40 blue marbles) / 8 blue marbles=15 red marbles.
answer: B. 15
Method 2: the ratio of red marbles to blue marbles is
ratio=number of red marbles / number of blue marbles
ratio=3/8
if we want to compute the number of red marbles we have to multiply the number of blue marbles by this ratio.
number of red marbles=ratio (red/blue)* number of blue marbles
number of red marbles=(3/8)*40=15
Answer: B.15
Answer:
base =5 because all angles=60, so an equilateral triangle
height=4.33
Step-by-step explanation:
height^2+1/2(5)^2=5^2
height^2+6.25=25
height^2=18.75
height=4.33
13x u add parentheses since two negatives positive
Answer:
s = 130 degrees
Step-by-step explanation:
decagon has a 1,440 degrees interior angles
equation: 1,440 = s + 1310
to find s, add all the known angles
⇒ s + 150 + 170 + 160 + 130 +120 + 160 + 105 + 160 +155
⇒ s + 1,310
equation:
s + 1310 = 1440
subtract each side by 1310
⇒ s + 1310 - 1310 = 1440 - 1310
⇒ s = 130