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:
1 decilitre
Step-by-step explanation:
You can look up charts for these. Look up litre chart
This will leave you with
140 = 2(40) + 2x
60 = 2x
30= x
So the length is 30.
279ft/9sec = xft/1sec
Cross multiply to get
9x = 279 divide by 9
x = 31
31 feet per second
Answer:
For part a)
130 = 10/2[2a+(10-1)d]
Simplify, u get
2a + 9d = 26.................(1)
Also U5 = a + (5-1)d = 3a
Simplify, u get
a= 2d...................(2)
Substituting for a in equation 1,
2(2d)+9d= 26
Solving for d, we get
d = 2
In part b) substituting for d in equation 2 to get the first term
a = 2(2) = 4
Part c) the no. of terms required can be obtained by solving
28 = 4+(n-1)2
n = 13
