Answer: e) 6
Step-by-step explanation:
Let x be mother + children = 18
Father's age = 38
Average age of the family = 14
38 + 18x /( x + 1 )= 14
Opening the bracket
38 + 18x = 14x + 14
Collecting like terms
24 = 4x
x = 6
no of children in the family is 6.
Answer:
Step-by-step explanation:
If all 21 coins were dimes, she'd have $2.10. But she has 90 more cents than that. Now for each coin that's a quarter, not a dime, she has 15 cents more. 90/15= 6. So there are 6 quarters, and 21-6 = 15 dimes.
Now we do it backwards to see if it's right. 6 quarters is $1.50, 15 dimes is $1.50, add those together and you get $3. So it's right. 6 quarters, 15 dimes.
Answer:
x = friends that paid discount price = 8
y = friends that paid regular price = 4
Step-by-step explanation:
Let
x = friends that paid discount price
y = friends that paid regular price
x + y = 12 (1)
6x + 8y = 80 (2)
From (1)
x = 12 - y
Substitute x = 12 - y into (2)
6x + 8y = 80 (2)
6(12 - y) + 8y = 80
72 - 6y + 8y = 80
- 6y + 8y = 80 - 72
2y = 8
y = 8/2
y = 4
Substitute y = 4 into (1)
x + y = 12 (1)
x + 4 = 12
x = 12 - 4
x = 8
x = friends that paid discount price = 8
y = friends that paid regular price = 4
Answer:
0.08x = $5400-0.1x Add 0.1x to both sides of the equation.
0.18x = $5400 Divide both sides by 0.18
x = $3000 and $54000-$3000 = $24000
$3,000 is invested at 8%
$2,400 is invested at 10%
Step-by-step explanation:
Hey!
This could be rewritten as:
2x + 1 + 5x
We can add like terms together:
7x + 1