Question

Если в следующем году маме увеличат зарплату на 20%, то доходы семьи возрастут на 6%, если папе, - то на 10%. А если бабушке увеличат пенсию на 20%, то доходы семьи увеличатся на 3200 рублей. Каков месячный доход семьи в этом году, если он состоит из зарплат мамы, папы и пенсии бабушки?

Answer 1

1500 - это 100%
пенсия после повышения - это 120%
чтобы найти пенсию пропорцию составляем: 1500*120% = пенсия после повышения*100%
Отсюда получается, что пенсия после повышения =1500 * 120%/100% или 1500*1,2/1 = 1800 рублей

Answer 2

Calculation of Family Income Increase

To calculate the monthly income of the family, we need to consider the salary increase for the mother, father, and the grandmother's pension increase.

Let's assume the current monthly income of the family is X rubles.

If the mother's salary increases by 20%, the family's income will increase by 6%. If the father's salary increases by 20%, the family's income will increase by 10%. If the grandmother's pension increases by 20%, the family's income will increase by 3200 rubles.

Let's calculate the monthly income of the family:

1. Increase in family income due to the mother's salary increase: - The family income will increase by 6% if the mother's salary increases by 20%. - This means the increase in family income due to the mother's salary increase is 6% of X rubles. - Mathematically, this can be represented as 0.06 * 0.2 * X = 0.012X.

2. Increase in family income due to the father's salary increase: - The family income will increase by 10% if the father's salary increases by 20%. - This means the increase in family income due to the father's salary increase is 10% of X rubles. - Mathematically, this can be represented as 0.1 * 0.2 * X = 0.02X.

3. Increase in family income due to the grandmother's pension increase: - The family income will increase by 3200 rubles if the grandmother's pension increases by 20%. - Mathematically, this can be represented as 3200 = 0.2 * X.

Now, let's solve these equations to find the value of X, which represents the current monthly income of the family.

From equation 3, we can solve for X: 0.2 * X = 3200 X = 3200 / 0.2 X = 16,000 rubles

Therefore, the current monthly income of the family is 16,000 rubles.

Please note that this calculation assumes that the increases in salary and pension are applied to the current income and pension levels, and there are no other changes in the family's income.

Summary: The monthly income of the family in this year is 16,000 rubles.