Jeff donated 30/100*300 = <<30/100*300=90>>90 pencils.
He remained with 300-90 = <<300-90=210>>210 pencils.
Vicki had twice as many pencils as Jeff, meaning he had 2*300 = <<2*300=600>>600 pencils.
When Vicki donated 3/4 of his pencils, he gave away 3/4*600= <<3/4*600=450>>450 pencils.
Vicki remained with 600-450=<<600-450=150>>150 pencils.
Together, Jeff and Vicki remained with 150+210 = <<150+210=360>>360 pencils.
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