Question

1. $15div3 - 2$ 5. $20div(2\times2)$ 6. $21 - 10 + 4$

Explanation:

Step1: Calculate division in 15÷3 - 2

$15\div3=5$

Step2: Calculate subtraction

$5 - 2=3$

Step3: Calculate multiplication in 20÷(2×2)

$2\times2 = 4$

Step4: Calculate division

$20\div4 = 5$

Step5: Calculate subtraction in 21 - 10+4

$21-10 = 11$

Step6: Calculate addition

$11 + 4=15$

Answer:

1. 3
2. 5
3. 15