Question

№1 Для покраски потолка требуется 270 г краски на 1м2. Краска продаётся в банках по 3кг.Сколько банок нужно купить для покраски потолка площадью 37м2? №2 - найти значения выражения log8 144 - log8 2,25

Answer 1

№1
270г=0,27 кг
0,27 кг* 37=9,99 кг
9,99:3=3,33 (банки). Но 0,33 банки купить нельзя. Значит, надо купить 4 банки.
№2
log8 144 - log8 2,25=log8 (144/2.25)=log8 64= 2.  (восемь в квадрате будет 64.)

Answer 2

Answer 1:

To calculate the number of paint cans needed to paint a ceiling with an area of 37m², we need to determine the total amount of paint required and then divide it by the amount of paint in each can.

Given that 270g of paint is required for 1m² of ceiling, we can calculate the total amount of paint needed for 37m² as follows:

Total paint needed = 270g/m² * 37m² = 9990g

Since the paint is sold in cans of 3kg each, we need to convert the total paint needed to kilograms:

Total paint needed = 9990g = 9.99kg

To find the number of cans needed, we divide the total paint needed by the amount of paint in each can:

Number of cans needed = Total paint needed / Amount of paint in each can Number of cans needed = 9.99kg / 3kg ≈ 3.33 cans

Since we cannot purchase a fraction of a can, we need to round up to the nearest whole number. Therefore, we would need to buy 4 cans of paint to cover a ceiling with an area of 37m².

Answer 2:

To find the value of the expression log8 144 - log8 2.25, we can use the logarithmic properties.

The logarithmic property we will use is:

log base a (b) - log base a (c) = log base a (b/c)

Using this property, we can rewrite the expression as:

log8 (144/2.25)

To simplify further, we can calculate the value of 144/2.25:

144/2.25 ≈ 64

Therefore, the expression log8 144 - log8 2.25 is equivalent to log8 64.

To find the value of log8 64, we need to determine what power of 8 equals 64. In other words, we need to find x in the equation 8^x = 64.

We can rewrite 64 as a power of 8:

64 = 8^2

Therefore, log8 64 = 2.

Hence, the value of the expression log8 144 - log8 2.25 is 2.