Charlotte and Layla are workers in a factory making widgets. Layla can make 20 widgets per day in the factory. Charlotte is able to produce 10% fewer widgets per day than Layla. How many widgets can Charlotte make per day?

What is the missing step in this proof ?

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?

Tamar is measuring the sides and angles of tuv to determine whether it is congruent to the triangle below. which pair of measurements would eliminate the possibility that the triangles are congruent