Solve (1+4+5+6+7+8+9+10+11+12+13+14+15)div15

$$(1+4+5+6+7+8+9+10+11+12+13+14+15) \div 15$$

Evaluate

$$\frac{23}{3}\approx 7.666666667$$

Solution Steps

Add 1 and 4 to get 5.

$$\frac{5+5+6+7+8+9+10+11+12+13+14+15}{15}$$

Add 5 and 5 to get 10.

$$\frac{10+6+7+8+9+10+11+12+13+14+15}{15}$$

Add 10 and 6 to get 16.

$$\frac{16+7+8+9+10+11+12+13+14+15}{15}$$

Add 16 and 7 to get 23.

$$\frac{23+8+9+10+11+12+13+14+15}{15}$$

Add 23 and 8 to get 31.

$$\frac{31+9+10+11+12+13+14+15}{15}$$

Add 31 and 9 to get 40.

$$\frac{40+10+11+12+13+14+15}{15}$$

Add 40 and 10 to get 50.

$$\frac{50+11+12+13+14+15}{15}$$

Add 50 and 11 to get 61.

$$\frac{61+12+13+14+15}{15}$$

Add 61 and 12 to get 73.

$$\frac{73+13+14+15}{15}$$

Add 73 and 13 to get 86.

$$\frac{86+14+15}{15}$$

Add 86 and 14 to get 100.

$$\frac{100+15}{15}$$

Add 100 and 15 to get 115.

$$\frac{115}{15}$$

Reduce the fraction \frac{115}{15} to lowest terms by extracting and canceling out 5.

$$\frac{23}{3}$$

Factor

$$\frac{23}{3} = 7\frac{2}{3} = 7.666666666666667$$