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# What is the sum of the first 40 even positive integers?

### Question

What is the sum of the first 40 even positive integers?

A) 1,600

B) 1,560

C) 820

D) 1,640

E) 400

### Explanation:

The formula to be used is:
$$\text{N} + 1 \times \cfrac{\text{N}}{2} \times 2$$
$$\text{N} = 40$$
$$40 + 1 \times \cfrac{40}{2} \times 2$$

$$41 \times \cfrac{40}{2} \times 2$$
$$\cfrac{1640}{2} \times 2$$
$$820 \times 2$$
Therefore, the sum of the first 40 even positive integers $$= 1640$$

Explanation provided by Pirisola Ayomikun

## Dicussion (1)

• The formula to be used is:
$$\text{N} + 1 \times \cfrac{\text{N}}{2} \times 2$$
$$\text{N} = 40$$
$$40 + 1 \times \cfrac{40}{2} \times 2$$

$$41 \times \cfrac{40}{2} \times 2$$
$$\cfrac{1640}{2} \times 2$$
$$820 \times 2$$
Therefore, the sum of the first 40 even positive integers $$= 1640$$