Y cymedr
\({Cymedr}~=~{cyfanswm~y~rhifau}\div{nifer~y~rhifau}\)
Enw arall ar gymedr y rhifau yw rhif cymedrig.
Question
Mae pum ffrind yn cymharu eu marciau mewn prawf Ffrangeg. Dyma nhw:
| Enw | Marc |
| Angharad | \({41}\) |
| Betsan | \({54}\) |
| Llywelyn | \({79}\) |
| Dei | \({26}\) |
| Anna | \({65}\) |
| Enw | Angharad |
|---|---|
| Marc | \({41}\) |
| Enw | Betsan |
|---|---|
| Marc | \({54}\) |
| Enw | Llywelyn |
|---|---|
| Marc | \({79}\) |
| Enw | Dei |
|---|---|
| Marc | \({26}\) |
| Enw | Anna |
|---|---|
| Marc | \({65}\) |
Beth ydy鈥檙 marc cymedrig?
\(Cymedr~=~({41} + {54} + {79} + {26} + {65})\div{5}\)
\(= {265}\div{5}\)
\(={53}\)
Question
Mae deis yn cael ei daflu \({10}\) gwaith, gan roi鈥檙 canlyniadau hyn:
\({3},~{5},~{1},~{2},~{6},~{4},~{2},~{5},~{6},~{1}\)
Beth ydy鈥檙 sg么r cymedrig?
I gael yr ateb, adia鈥檙 rhifau gyda鈥檌 gilydd a rhannu鈥檙 cyfanswm 芒 nifer y rhifau:
\(Cymedr~=~({3} + {5} + {1} + {2} + {6} + {4} + {2} + {5} + {6} + {1})\div{10}\)
\({35}\div{10} = {3.5}\)