Answer:
80
Step-by-step explanation:
Think of it as a Venn diagram. One circle is the people who like dogs, and one circle is the people who like cats. The overlap is people who like both dogs and cats.
190 people in the survey said they like dogs. That includes the people who like both dogs and cats.
141 people in the survey said they like cats. That includes the people who like both dogs and cats.
If we simply add the two numbers together, we'll be counting the overlap twice. So to find the total number of people who like dogs or cats, we have to subtract one overlap.
dogs or cats = 190 + 141 − x
Therefore:
190 + 141 − x + 88 = 339
419 − x = 339
x = 80
80 people said they liked both cats and dogs.
Answer:
10
Step-by-step explanation:
Let c = sum of ages of all children.
mean age of all children = c/15 = 7
c = 15 * 7 = 105
The sum of the ages of all children is 105.
Let b = sum of ages of the 9 boys.
mean age of boys = b/9 = 5
b = 9 * 5 = 45
The sum of the ages of the boys is 45.
The sum of the ages of the girls is c - b.
c - b = 105 - 45 = 60
The number of girls is 15 - 9 = 6
mean age of girls = (sum of ages of the girls)/(number of girls) =
= 60/6 = 10
3x+7=3x+2 (cancel equal terms)
7=2 ( the statement is false)
53-49=4
4 times 12=48. the unknown number is 48