15
63 x 5 = 315
315/20 = 15.75
hence, 15 $20 bills
Answer:
The sum of two negative integers is always negative.
Step-by-step explanation:
For example, add -1+-1 which =-2, which are the smallest neggative numbers possible.-100+-100=-200, and -4+-4=-8, so you see that the sum of two negative integers should always be negative.
Answer:
30 grams
Step-by-step explanation:
half life is 60 days so every 60 days the amount 480 grams will be half
in 240 days will decay 240 /60 = 4 times
once 480 /2 = 240
twice 240 /2 = 120
trice 120 / 2 = 60
four times 60/2 = 30 grams will be left
Answer:
Step-by-step explanation:
In the diagram shown, the measure of angle 1 is oppositely directed to angle 2 and oppositely directed angles are equal.
Hence <1 = <3
Given < 1 = 3x-1 and <3 = 2x+9
Hence 3x-1 = 2x+9
collect like terms
3x-2x = 9+1
x = 10°
Since <1 = 3x-1
on substituting x = 10
<1 = 3(10)-1
<1 = 30-1
<1 = 29°
<1+<2 = 180 (angle on a straight line)
29+<2 = 180
<2 = 180-29
<2 = 151°
Similarly, on substituting x = 10 into <3
<3 = 2x+9
<3 = 2(10)+9
<3 = 20+9
<3 = 29°
<3+<4 = 180 (angle on a straight line)
29+<4 = 180
<4 = 180-29
<4 = 151°