Ffocws rhifedd.
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Askew, Mike.
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Bodedern : Gwasg Taf,
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Argraffiad Saesneg gwreiddiol = Original English edition : Oxford : Rigby, 2000.
Addasiad Cymraeg: Awdurdod Cymwysterau, Cwricwlwm ac Asesu Cymru = Welsh adaptation: Qualifications, Curriculum and Assessment Authority for Wales.
Numeracy