Peter the optician sees 16 patients one Tuesday.4 are neither short nor long sighted, the total number of short sighted patients is 2 more than the total number of long sighted, how many patients can be short sighted, how many long sighted, and how many will require varifocal lenses

Solution:

Number of patients  having neither long nor shortsightedness = 4

Let number of patients having long sightedness be "x"

The total number of short sighted patients is 2 more than the total number of long sighted

Therefore,

Number of patient having shortsightedness = x + 2

Peter the optician sees 16 patients one Tuesday

Total number of patients = 16

Therefore,

x + x + 2 + 4 = 16

2x + 6 = 16

2x = 16 - 6

2x = 10

x = 5

Number of patients having longsightedness = x = 5

Number of patient having shortsightedness = x + 2 = 5 + 2 = 7

Patients requiring varifocal lenses will be = 5 + 7 = 12  

step-by-step explanation:

we can use this expression to calculate the energy gain as a particle moves with a field or the energy loss as it moves against it. (note that it is also used to define the electron-volt, a unit of energy equal to that gained by an electron as it falls through a pd of 1 v, i.e. w = 1 ev = 1.6 10-19 c 1 v = 1.6 10-19j).in fact this expression is really nothing more than the statement that potential is the potential energy per unit charge. in this case, v= w/qis simply stating that the change in potential energy(or work done) per unit charge is equal to the change in potential (or potential difference), v.student questions: uniform electric fields2electron beamcathode+5 kvanode0 v

explanation:

step-by-step explanation: