N=number of nickels
d=number of dimes
q=number of quarters
example
if n:d=3:8
lets say n=3 and d=8
3*8=8*3
so
8n=3d
slightly confusing but go with it, it migh make sense or it might not
n:d=3:8
8n=3d
d:q=4:5
5d=4q
solve for one of them
solve for nickels in first and quarters in second
8n=3d, n=(3/8)d
5d=4q, (4/5)d=q
5n+10d+25q=690
divide by 5 to make it easeir
n+2d+4q=138
sub (3/8)d for n
sub (4/5)d for q
(3/8)d+2d+5(5/4)d=138
(3/8)d+2d+25/4d=138
3/8+2+25/4=
3/8+16/2+50/8=
69/8
(69/8)d=138
times both sides by 8
69d=1104
divide both sides by 69
d=16
16 dimes
sub back
(5/4)d=q
(5/4)16=q
80/4=q
20=q
(3/8)d=n
(3/8)16=n
48/8=n
6=n
6 nickles
16 dimes
20 quarters
yah
Answer:
I think it is A
Step-by-step explanation:
ust remember to divide the diameter by two to get the radius. If you were asked to find the radius instead of the diameter.
7 is 35% of x.
Thus, since 35% = 35/100,
35% of x is 7, so 35/100 * x = 7.
35x/100 = 7
35x=700
x = 20
7 is 35% of 20.
<u>Solution</u><u> </u><u>1</u><u> </u><u>:</u><u>-</u>
>> -3 (3 - x) = 2x + 5
>> -3 × (3 - x) = 2x + 5
>> -9 + 3x = 2x + 5
>> 3x - 2x = 9 + 5
>> x = 14
<u>Solution</u><u> </u><u>2</u><u> </u><u>:</u><u>-</u>
>> -6 - 9p = 3p
>> -9p - 3p = 6
>> -12p = 6
>> p = -1/2
<u>Solution</u><u> </u><u>3</u><u> </u><u>:</u><u>-</u>
>> -5 (-4 - a) = 3a + 8
>> -5 × (-4 - a) = 3a + 8
>> 20 + 5a = 3a + 8
>> 5a - 3a = 8 - 20
>> 2a = -12
>> a = -12 / 2
>> a = -6
<u>Solution</u><u> </u><u>4</u><u> </u><u>:</u><u>-</u>
>> s - 6 = -5s
>> s + 5s = 6
>> 6s = 6
>> s = 6 / 6
>> s = 1
