0.3 imes 0.7 = 0.21. Solve 0.7 imes 0.6? 8. The average of 1, 2 and 3 is 2. What is the average of 4, 5, 7, 8, and 11? 9. Two angles of a triangle are 60^ exto and 65^ exto; Find the third angle. 10.

$7 \times 6 = 42$.

0.7 has one decimal place.

0.6 has one decimal place.
Total decimal places $= 1 + 1 = 2$.

Starting from the right of 42, move the decimal point 2 places to the left.
This gives 0.42.

8. The average of 1, 2 and 3 is 2. What is the average of 4, 5, 7, 8, and 11?

Sum $= 4 + 5 + 7 + 8 + 11 = 35$.

There are 5 numbers.

Average $= \frac{35}{5} = 7$.

9. Two angles of a triangle are $60^\circ$ and $65^\circ$; Find the third angle.

Let the third angle be $\theta$.

Sum of known angles $= 60^\circ + 65^\circ = 125^\circ$.

$\theta = 180^\circ - 125^\circ = 55^\circ$.

10. What is the next number in the sequence 4, 7, 10, 13, 16?

$7 - 4 = 3$
$10 - 7 = 3$
$13 - 10 = 3$
$16 - 13 = 3$
The pattern is an addition of 3 to the previous term.

Next number $= 16 + 3 = 19$.

11. A bag was bought for 5000 FRS and sold at a gain of 500frs. What is the % gain?

Cost Price (CP) $= 5000$ FRS.
Gain $= 500$ FRS.

$\text{Percentage Gain} = \frac{\text{Gain}}{\text{Cost Price}} \times 100\%$.

$\text{Percentage Gain} = \frac{500}{5000} \times 100\% = \frac{1}{10} \times 100\% = 10\%$.

12. The area of a square field is $64\text{m}^2$. Find the dimension of the side of the field.

Area $= \text{side} \times \text{side} = s^2$.

$s^2 = 64\text{m}^2$.

$s = \sqrt{64\text{m}^2} = 8\text{m}$.

13. If 0.4 of my money is 3000 FRS. What is the total amount of my money?

Set up the equation based on the given information.
$0.4 \times M = 3000$.

$0.4 = \frac{4}{10} = \frac{2}{5}$.
So, $\frac{2}{5} M = 3000$.

$M = 3000 \times \frac{5}{2} = 1500 \times 5 = 7500$.
The total amount of money is 7500 FRS.

14. The difference between 7 and 3 is 4. What is the difference between 2.1 and 0.796?

The numbers are 2.1 and 0.796.

Difference $= 2.1 - 0.796$.

The difference is 1.304.