Question

Задание 1: Решил уравнения 4класс 823-25-х=208 5*6*а=2100 Х÷5=900÷30 Задание 2: Решите задачу. Составьте обратную ей задачу и решил её. Теплоход по течению реки плыл 4 ч со скоростью 80 км/ч, а на обратном пути он плыл 5 ч. С какой скоростью Теплоход плыл на обратном пути? Задание 3 . Для национального костюма мастерская израсходовала 5 упаковок бисера, по 150 бусинки в каждой. После этого ей осталось пришить ещё 280 бусинки. Сколько всего бусинки по требовалось мастерице?

Answer 1

Ответ:

1)823-25-х=208

798-х=208

х=798-208

х=590

2)t1-4ч

v1-40 км\ч

t2-5ч

V2-?

V=s\t

80*4\5=320\5=64 км\час

Пошаговое объяснение:

Answer 2

Задание 1
823-25-х=208
798-х=208
-х=208-798
-х=-590
Х=590


5*6*а=2100
30а=2100
А=70





х\5=900\30
30х=4500
х=150

Answer 3

Task 1: Solving Equations

To solve the given equations, let's go through them one by one:

1. Equation 1: 823 - 25 - x = 208 To solve for x, we need to isolate it on one side of the equation. Let's simplify the equation step by step: - Subtract 823 and 25 from both sides: 823 - 25 - x - 823 - 25 = 208 - 823 - 25 - Simplify: -x = -640 - Multiply both sides by -1 to isolate x: -1 * -x = -1 * -640 - Simplify: x = 640

Therefore, the solution to the equation 823 - 25 - x = 208 is x = 640.

2. Equation 2: 5 * 6 * a = 2100 To solve for a, we need to isolate it on one side of the equation. Let's simplify the equation step by step: - Multiply 5, 6, and a: 5 * 6 * a = 2100 - Simplify: 30a = 2100 - Divide both sides by 30 to isolate a: (30a) / 30 = 2100 / 30 - Simplify: a = 70

Therefore, the solution to the equation 5 * 6 * a = 2100 is a = 70.

3. Equation 3: x ÷ 5 = 900 ÷ 30 To solve for x, we need to isolate it on one side of the equation. Let's simplify the equation step by step: - Divide both sides by 5: (x ÷ 5) = (900 ÷ 30) ÷ 5 - Simplify: x = (900 ÷ 30) ÷ 5 - Simplify further: x = 30 ÷ 5 - Simplify: x = 6

Therefore, the solution to the equation x ÷ 5 = 900 ÷ 30 is x = 6.

Task 2: Reverse Problem and Solution

The original problem states that a boat traveled downstream for 4 hours at a speed of 80 km/h and then traveled upstream for 5 hours. We need to find the speed of the boat on the return trip.

To solve this problem, we can use the formula: speed = distance / time.

Let's assume the distance traveled downstream and upstream is the same. Therefore, the distance traveled downstream is equal to the distance traveled upstream.

Let's say the distance is d km.

1. Downstream trip: - Speed = 80 km/h - Time = 4 hours - Distance = Speed * Time = 80 km/h * 4 hours = 320 km

2. Upstream trip: - Speed = ? - Time = 5 hours - Distance = Speed * Time = d km

Since the distance traveled downstream and upstream is the same, we can equate the distances:

320 km = d km

Therefore, the distance traveled downstream and upstream is 320 km.

Now, let's solve for the speed of the boat on the return trip:

Speed = Distance / Time = 320 km / 5 hours = 64 km/h

Therefore, the speed of the boat on the return trip is 64 km/h.

Task 3: Bead Calculation

The workshop used 5 packs of beads, with 150 beads in each pack, for a total of 5 * 150 = 750 beads.

After using these beads, the workshop still needs to sew on an additional 280 beads.

Therefore, the total number of beads required by the workshop is 750 + 280 = 1030 beads.