Simply it as follows:
1 + 39 = 40
2 + 38 = 40 etc
18 + 22 = 40
19 + 21 = 40
There are 19 of these plus 40 itself . . .therefore 20 of them
20 x 40 = 800
And finally the last number not used, 20
Therefore 800 + 20 = 820
Estimate 285 as 300 and 11 as 10 so
we have 300 / 10 = 30
Its C
Answer:
x=-2
Step-by-step explanation:
If x always = -2, it is a straight vertical line which means it is parallel to the y axis
Answer:
1 st questions answer is third option
while the answer of other question is 3
Step-by-step explanation:
2nd qestions explanation
put value of x=2 in equation as x-2=0 from equation
(2)^3-6(2)^2+a2+10=2
8-24+a2+10=0
2a=-18+24
2a=6
a=3
Answer:
<u>The present age of the mother is 30 years old</u>
Step-by-step explanation:
Age of Jane = x
Age of Billy = 5x (Billy is five times as old as Jane)
Age of Sara = 15x (Their mother is now three times as old as Billy)
In 2 years Sara will be eight times as old as Jane, therefore:
15x + 2 = 8 (x + 2)
15x + 2 = 8x + 16
15x - 8x = 16 - 2
7x = 14
x = 14/7
x = 2 ⇒ 5x = 10x ⇒ 15x = 30
Jane's present age is 2, Billy's present age is 10 and Sara's present age is 30
<u>The present age of the mother is 30 years old</u>
