At the start of the diet keirin weighted 14 stone 13 pounds three months later he weighted 13 stone 10 pounds there are 14 pounds in a stone.

The amount of weight he has lost in 3 months is 1.215 stone or 1 stone 3 pounds

Step-by-step explanation:

From the above question, we are to calculate the amount of weight he has lost in three months

1 stone = 14 pounds

Let's convert all the weight lost to stone

At the start of the diet keirin weighted 14 stone 13 pounds

14 pounds = 1 stone

13 pounds = x

Cross Multiply

14x = 13

x = 13/14

x = 0.9285714286 stone

Approximately = 0.929 stone

Hence:

14 stone 13 pounds = 14 + 0.929 = 14.929 stone

Three months later he weighted 13 stone 10 pounds

14 pounds = 1 stone

10pounds = x

Cross Multiply

14x = 10

x = 10/14

x = 0.7142857143 stone

Approximately = 0.714 stone

Hence:

13 stone 10 pounds = 13 + 0.714 = 13.714 stone

The amount of weight he has lost is calculated as:

14.929 stone - 13.714 stone = 1.215 stone or 1 stone 3 pounds

15

step-by-step explanation:

we are given the following expression and we are to solve it and find the product:

-13 × (-5)

solving the given expression in the standard order of solving a mathematical expression, beginning with the opening of brackets and then multiplying the terms and changing their signs.

-3 × -5 = 15 (answer is positive because when negative is multiplied with negative, it gives a positive answer)