Answer:
35 [$]
Step-by-step explanation:
1) if Peter's sum is p and Jacky's is j, then the ratio 5:2 in the condition can be written j/p=5/2;
2) the phrase 'after Jacky gave 15 dolls to Peter, they have an equal number of dolls' can be written as j-15=p;
3) using the two above it is possible to make up the system of two equations:

4) finally, the have together 10+25=35 doll-s.
Answer:
Minimum number of units sold to make profit is equal to 20
Step-by-step explanation:
Revenue earned by the company as a function of number of units sold as x:
R(x) = 0.55x
Cost for selling units as a function of number of units sold as x:
C(x) = 10 + 0.05x
<em>Net profit earned by the company = (Revenue earned by the company) - (Cost of selling units)</em>
P(x) = (0.55x) - (10 + 0.05x)
P(x) = 0.55x - 10 - 0.05x
P(x) = 0.5x - 10
To earn profit the following condition should satisfy: P(x) ≥ 0
0.5x - 10 ≥ 0
0.5x ≥ 10
x ≥ 
x ≥ 20
Answer:
£1920
Step-by-step explanation:
The amount she spent in 2016 is 20% less than 2017. 20% less than is the same as 80% of the amount she spent in 2017. So, to find how much she spent in 2016, multiply 2400 by 0.80 (the decimal form of 80%):
2400 * 0.8 = 1920
Emily spent £1920 on holiday in 2016.
I hope this helps :)