Question

За 5 ручок і 4 олівці заплатили 10 грн . Скільки коштує одна ручка и скільки олівець , якщо 3ручки дорожчі за 2 олівці на 1 грн 60 коп ? Помогите пожалуйста нужно срочно ​

Answer 1

Ответ:

1 грн - карандаш;

1,2 грн - ручка.

Объяснение:

"За 5 ручек и 4 карандаша заплатили 10 грн . Сколько стоит одна ручка и сколько карандаш , если 3  ручки дороже 2 карандаша на 1 грн 60 коп. Помогите пожалуйста нужно срочно ​"

х- стоимость ручки;

у- стоимость карандаша;

Составляем уравнения:

5х+4у=10;  [*3]

3х-2у=1,6.  [*5]

Это уже система.

15x+12y=30;

15x-10y=8;

Вычитаем:

12y+10y=30-8;

22y=22;

y=1 - стоимость карандаша.

3x-2*1=1.6;

3x=3,6

x=1,2,

Answer 2

To solve this problem, let's assign variables to the cost of one pen and one pencil. Let's say the cost of one pen is P and the cost of one pencil is C.

From the given information, we can form two equations:

Equation 1: 5P + 4C = 10 (since 5 pens and 4 pencils were bought for 10 UAH) Equation 2: 3P = 2C + 1.60 (since 3 pens are more expensive than 2 pencils by 1 UAH and 60 kopecks)

We can solve this system of equations to find the values of P and C.

Solving the System of Equations

To solve this system of equations, we can use the substitution method. Let's solve Equation 2 for P:

3P = 2C + 1.60 P = (2C + 1.60) / 3

Now, substitute this expression for P in Equation 1:

5((2C + 1.60) / 3) + 4C = 10

Simplifying this equation will give us the value of C. Let's solve it step by step:

5(2C + 1.60) + 12C = 30 10C + 8 + 12C = 30 22C + 8 = 30 22C = 22 C = 1

Now that we have the value of C, we can substitute it back into Equation 2 to find the value of P:

3P = 2(1) + 1.60 3P = 2 + 1.60 3P = 3.60 P = 1.20

Answer

Therefore, one pen costs 1.20 UAH and one pencil costs 1 UAH.

Please let me know if you need any further assistance!