Answer:
Step-by-step explanation:
Bánh mì 1.5 đô
Cà phê 2 đô
Answer:
21. x = 5, 23.
Step-by-step explanation:
Answer:
No
Step-by-step explanation:
Substitute by x = 2 and y = - 1
You will get 2*2 + (-1) = 3 not 5
Then it doesn't lie
Answer:
3 × 4/9
Step-by-step explanation:
Remember that 4/4 is equal to 1, so 3 × 4/4 = 3
15 is bigger than 8, so we know that 15/8 is equal to 1 point something, you can find out the answer by a simple division, once you know the answer (1.875), you multiply it by 3, and get 5.625, this is larger than 3 so it is not the answer.
4 is smaller than 9, so we know that 4/9 is equal to 0 point something, again, we divide and get 0.444..., now we know that multypling something by 0 pint something is almost the same as dividing, so we can that this result is less than 3 (its 1.333).
1 and 1/8 is a mixed fraction so we know it is larger than 1, meaning that if we multiply it by 3, we will get a number larger than 3 (3.375)
