Guppies: u
Goldfish: o
3 times as many guppies as goldfish
3*o = u (there are more guppies than goldfish)
o + u = 20
o = 20 - u
Substitute in (20 - u) for o in the first equation and solve:
3* (20 - u) = u
60 - 3u = u
60 = 4u
u = 15
He has 15 guppies. Then substitute in the number of guppies into either equation to find the number of goldfish:
o + u = 20
o + (15) = 20
o = 5
Hope this helps! :)
If the owner is giving a free cupcake to every 4th customer. Then the easiest way to do this is to follow the 4 times table: 4, 8, 12, 16, 20
So the answer is No, Emma will not be receiving a free cupcake as she is the 17th customer and doesn't fall into the 4th customer pattern.
precedence is:
1 Parentheses (simplify inside 'em)
2 Exponents
3 Multiplication and Division (from left to right)
4 Addition and Subtraction (from left to right)
(7+41) = 48
48 ÷ 2 = 24
24 -15 = 9
