The phrase "equal that of" is correct and usable in written English
It can be used to compare the equality of one thing to another, often in formal or academic contexts.
Example: "The performance of the new software is equal that of the previous version."
Alternatives: "equivalent to" or "on par with"
Indeed, Deen's scepticism would equal that of the sternest critic.
In this case, though, the contestants are machines, with their own down-home charisma, even if it doesn't equal that of Michael Phelps.
Vaccine is being shipped now, and the government insists that the vaccine supply this year will equal that of last year.
There are hundreds of thousands of people affected by genetic disorders whose intellectual acuity and capability equal that of the lawyers you mention.
Even so, Mr. Schick estimated that the catch would equal that of a typical six-month season, about 1,800 metric tons, or nearly four million pounds.
His salary will equal that of Allen Wheat, chief executive of Credit Suisse First Boston, the group's investment bank, which will absorb Donaldson Lufkin.
Over the past two years there has been a spectacular transmogrification to equal that of the Born, Sant Pere's chichi neighbour.
He doesn't suppress stories, he proliferates them, giving relationships among the cast and crew and passersby a weight to equal that of the scripted action.
"Until we have created a romance of peace that would equal that of war, violence will not disappear from people's lives," Kessler told friends at war's end.
The number of Mormons throughout the world may soon equal that of Jews, and, indeed, many see a parallel between the two faiths.
Radiohead and Phish were returning headliners — Radiohead from 2006 and Phish from 2009 — and this year's overall lineup did not quite equal that of previous years.
